bluuebunny/crossref_metadata_2025 huggingface dataset:
Classifying Galaxy Morphologies with Few-shot Learning
Authors: Zhang Zhirui , Zou Zhiqiang , Li Nan , Chen Yanli
Published: February 2022

The taxonomy of galaxy morphology is critical in astrophysics as the morphological properties are powerful tracers of galaxy evolution. With the upcoming Large-scale Imaging Surveys, billions of galaxy images challenge astronomers to accomplish the classification task by applying traditional methods or human inspection. Consequently, machine learning, in particular supervised deep learning, has been widely employed to classify galaxy morphologies recently due to its exceptional automation, efficiency, and accuracy. However, supervised deep learning requires extensive training sets, which causes considerable workloads; also, the results are strongly dependent on the characteristics of training sets, which leads to biased outcomes potentially. In this study, we attempt Few-shot Learning to bypass the two issues. Our research adopts the data set from the Galaxy Zoo Challenge Project on Kaggle, and we divide it into five categories according to the corresponding truth table. By classifying the above data set utilizing few-shot learning based on Siamese Networks and supervised deep learning based on AlexNet, VGG_16, and ResNet_50 trained with different volumes of training sets separately, we find that few-shot learning achieves the highest accuracy in most cases, and the most significant improvement is 21% compared to AlexNet when the training sets contain 1000 images. In addition, to guarantee the accuracy is no less than 90%, few-shot learning needs ∼6300 images for training, while ResNet_50 requires ∼13,000 images. Considering the advantages stated above, foreseeably, few-shot learning is suitable for the taxonomy of galaxy morphology and even for identifying rare astrophysical objects, despite limited training sets consisting of observational data only.
Solar and geoneutrinos
Authors: Ludhova L , Agostini M , Altenmüller K , Appel S , Atroshchenko V , Bagdasarian Z , Basilico D , Bellini G , Benziger J , Biondi R , Bravo D , Caccianiga B , Calaprice F , Caminata A , Cavalcante P , Chepurnov A , D’Angelo D , Davini S , Derbin A , Giacinto A Di , Marcello V Di , Ding X.F , Ludovico A Di , Noto L Di , Drachnev I , Formozov A , Franco D , Galbiati C , Ghiano C , Giammarchi M , Goretti A , Göttel A.S , Gromov M , Guffanti D , Ianni Aldo , Ianni Andrea , Jany A , Jeschke D , Kobychev V , Korga G , Kumaran S , Laubenstein M , Litvinovich E , Lombardi P , Lomskaya I , Lukyanchenko G , Lukyanchenko L , Machulin I , Martyn J , Meroni E , Meyer M , Miramonti L , Misiaszek M , Muratova V , Neumair B , Nieslony M , Nugmanov R , Oberauer L , Orekhov V , Ortica F , Pallavicini M , Papp L , Pelicci L , Penek Ö , Pietrofaccia L , Pilipenko N , Pocar A , Raikov G , Ranalli M.T , Ranucci G , Razeto A , Re A , Redchuk M , Romani A , Rossi N , Schönert S , Semenov D , Settanta G , Skorokhvatov M , Singhal A , Smirnov O , Sotnikov A , Suvorov Y , Tartaglia R , Testera G , Thurn J , Unzhakov E , Villante F , Vishneva A , Vogelaar R.B , Feilitzsch F von , Wojcik M , Wurm M , Zavatarelli S , Zuber K , Zuzel G
Published: February 2022

Thanks to the progress of neutrino physics, today we are able of exploiting neutrinos as a tool to study astrophysical objects. The latter in turn serve as unique sources of elusive neutrinos, which fundamental properties are still to be understood. This contribution attempts to summarize the latest results obtained by measuring neutrinos emitted from the Sun and geoneutrinos produced in radioactive decays inside the Earth, with a particular focus on a recent discovery of the CNO-cycle solar neutrinos by Borexino. Comprehensive measurement of the pp-chain solar neutrinos and the first directional detection of sub-MeV solar neutrinos by Borexino, the updated 8B solar neutrino results of Super-Kamiokande, as well as the latest Borexino and KamLAND geoneutrino measurements are also discussed.
Cosmological constraints on heavy sterile neutrinos
Authors: Mastrototaro L
Published: February 2022

We consider heavy sterile neutrinos νs
, with mass in the range 10 MeV ∼ ms
∼ mπ
∼ 135 MeV, thermally produced in the early universe and freezing out after the QCD phase transition. The existence of these neutrinos may alter the value of the effective number of neutrino species N
eff, measured by the cosmic microwave background (CMB), and the 4He production during the BBN. We provide a detailed account of the solution of the relevant Boltzmann equations and we identify the parameter space constrained by current Planck satellite data and forecast the parameter space probed by future Stage-4 ground-based CMB (CMB-S4) observations.
Neutron-antineutron oscillations as a probe of baryogenesis
Authors: Fridell Kåre , Harz Julia , Hati Chandan
Published: February 2022

A signal of neutron-antineutron (

n
−

n
¯

) oscillations at experiments like the Deep Underground Neutrino Experiment or the European Spallation Source, would directly imply baryon number violation and will point towards physics beyond the Standard Model. The discovery of such a signal would have important implications for baryogenesis mechanisms in the early Universe, which can explain the observed baryon asymmetry of the Universe today. Here we discuss how an observed rate for

n
−

n
¯

oscillations can directly be correlated with the washout of baryon asymmetry in the early Universe and therefore, can probe high- and low-scale baryogenesis scenarios in synergy with collider searches.
A Model-Independent Radio Telescope Dark Matter Search
Authors: Keller A , O’Brien S , Kamdar A , Rapidis N , Leder A F , van Bibber K
Published: February 2022

A novel search technique for ultralight dark matter has been developed and initially carried out over a limited range of frequency in L-band, utilizing the recent Breakthrough Listen public data release of three years of observation with the Green Bank Telescope. The search concept depends only on the assumption of decay or annihilation of virialized dark matter leading to a quasi-monochromatic radio line, and additionally that the frequency and intensity of the line be consistent with very general expected properties of the phase space of our Milky Way halo. Specifically, the search selects for a line which exhibits a Doppler shift with position according to the solar motion through a static galactic halo, and similarly varies in intensity with position with respect to the halo profile. The analysis of the full L-, S-, C- and X-band dataset by this method is currently underway.
Combined Dark Matter searches from dwarf spheroidal galaxies observations by Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS
Authors: Kerszberg Daniel , Armand Céline , Charles Eric , Mauro Mattia di , Giuri Chiara , Harding J. Patrick , Miener Tjark , Moulin Emmanuel , Oakes Louise , Poireau Vincent , Pueschel Elisa , Rico Javier , Rinchiuso Lucia , Salazar-Gallegos Daniel , Tollefson Kirsten , Zitzer Benjamin
Published: February 2022

Dwarf spheroidal galaxies (dSphs) are ideal targets for Dark Matter (DM) indirect searches due to their high DM content and their negligible expected astrophysical background. In this presentation, we report on the combined analysis of the observations of 20 dSphs by Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS collaborations in the search for DM, focusing on the Weakly Interacting Massive Particles (WIMPs) scenario. The combined analysis allows us to maximize the sensitivity by combining individual data sets from all five experiments for which the energy ranges of the search overlap. New constraints, spanning a range of DM masses from 5 GeV to 100 TeV, on the velocity-weighted cross section for DM self annihilation will be presented.
The dark-PMT: a novel directional light Dark Matter detector based on vertically-aligned carbon nanotubes
Authors: Pandolfi F , Apponi A , Cavoto G , Mariani C , Rago I , Ruocco A
Published: February 2022

We present the ‘dark-PMT’, a novel detector concept based around a target made of vertically-aligned carbon nanotubes. The detector is sensitive to electron recoils induced by sub-GeV dark matter, and is expected to have directional sensitivity and to be unaffected by thermal noise, even at room temperature. The key feature is that nanotubes are made of graphene, which is a two-dimensional material: therefore, if a dark matter particle transfers enough energy to an electron in the carbon lattice to overcome the work function (4.7 eV), the electron will be ejected directly into the vacuum. Because of the strong density anisotropy of nanotubes, the electrons will be capable of leaving the target, without being reabsorbed, if travelling in the direction of the tube axes. The electrons will then be accelerated, and reach an energy of 5 keV before hitting an electron sensor. We report on the most recent advancements towards the construction of a dark-PMT: a novel, state-of-the-art facility for nanotube synthesis has been recently installed in Rome, and it is being used to produce high-quality nanotubes; and detailed characterizations of silicon sensors with keV electrons have been performed.
Probing dark matter-cosmic ray electron interactions with circular polarisation of photons
Authors: Cermeño Marina
Published: February 2022

Conventional indirect dark matter (DM) searches look for an excess in the electromagnetic emission from the sky that cannot be attributed to known astrophysical sources, but its polarisation has not been explored to date. In this proceeding, I argue that photon polarisation is an important feature to understand new physics interactions. Circular polarisation can be generated from Beyond the Standard Model interactions if they violate parity and there is an asymmetry in the number density of the initial state particles which participate in the interaction. I consider a simplified model for fermionic (Majorana) DM and study the circularly polarised gamma rays from DM cosmic ray electron interactions. I study the differential flux of positive and negative polarised photons from the Galactic Centre and show that the degree of circular polarization can reach up to 90%. Finally, I discuss the detection prospects of this signal in future experiments.
The ASTAROTH Project: enhanced low-energy sensitivity to Dark Matter annual modulation
Authors: Zani A. , Alessandria F. , Andreani A. , Castoldi A. , Coelli S. , Cortis D. , D’Angelo D. , Carlo G. Di , Frontini L. , Gallice N. , Ghisetti M. , Guazzoni C. , Liberali V. , Monti M. , Orlandi D. , Pasini A. , Pedrini D. , Prioli M. , Sorbi M. , Stabile A. , Statera M.
Published: February 2022

ASTAROTH is a novel R&D project which aims at improving the physics reach of future direct dark matter detection experiments based on NaI(Tl) scintillating crystals. There is a strong need to test the long standing DAMA positive observation of an annual modulation that could be due to Dark Matter (DM), with the same target material and in a model independent way. ASTAROTH aim is the enhancement of the sensitivity to the annual modulation signal, compared with present technology, by lowering the detection energy threshold in order to observe sub-keV recoils for the first time. This can be achieved by reading the scintillation light from the NaI(Tl) crystals with arrays of Silicon PhotoMultipliers (SiPM), and placing the detectors in a cryogenic environment. SiPMs feature lower dark noise than Photomultiplier Tubes (PMTs) at T < 150 K and allow for higher light collection. The cooling medium is liquid Argon, as it is an excellent scintillator that can be instrumented to act as a veto against several backgrounds.

Here we present the status of the ASTAROTH project, introducing the innovative design of the detector chamber that will be used for the demonstration of the technology. Then, we will show the preliminary results of our first ever measurements performed on a single NaI(Tl) crystal read out by one SiPM array in a cryogenic set-up cooled with liquid nitrogen.
Studying dark matter with MadDM: lines and loops
Authors: Massaro D. , Arina C. , Heisig J. , Maltoni F. , Mattelaer O.
Published: February 2022

Automated tools for the computation of amplitudes and cross sections have become the backbone of phenomenological studies beyond the standard model. We present the latest developments in MadDM, a calculator of dark-matter observables based on MadGraph5_aMC@NLO. The new version enables the fully automated computation of loop-induced annihilation processes, relevant for indirect detection of dark matter. Of particular interest is the direct annihilation into photons, γγ, γX. These processes lead to monochromatic gamma-ray lines that are smoking-gun signatures for dark-matter annihilation in our Galaxy. MadDM computes the predictions for the expected photon fluxes near Earth and derives constraints from the gamma-ray line searches by Fermi-LAT and HESS. As an application, we present the implications for the parameter space of the Inert Doublet Model.
Environmental noises in current and future gravitational-wave detectors
Authors: Badaracco Francesca
Published: February 2022

Gravitational–wave (GW) detectors are very sensitive instruments that suffer from a huge number of noises. If we aim to observe gravitational waves with earthbound detectors, we need to take care of every source that can prevent the observation. Seismic noise poses a huge challenge to the sensitivity in the the low-frequency band and it is tackled with suspensions and active controls. The low–frequency band can also be threatened by the so–called Newtonian noise, generated by the fluctuations of the gravity field. If this has not been a problem in the first generation gravitational-wave detectors, it will be so in the next runs and especially in the third–generation detectors, like the Einstein Telescope. We need then to be prepared to suppress as much as possible these noises, otherwise they might become the last wall for the sensitivity of our detectors. This manuscript will explore environmental noises with a particular detail on Newtonian and seismic noise and the techniques that we can employ to reduce their effects.
Constraining positron emission from pulsar populations with AMS-02 data
Authors: Orusa Luca , Manconi Silvia , Donato Fiorenza , Mauro Mattia Di
Published: February 2022

The cosmic-ray flux of positrons is measured with high precision by the space-borne particle spectrometer AMS-02. The hypothesis that pulsar wind nebulae (PWNe) can significantly contribute to the excess of the positron (e+) cosmic-ray flux has been consolidated after the observation of a γ-ray emission at TeV energies of a few degree size around Geminga and Monogem PWNe. In this work we undertake massive simulations of galactic pulsars populations, adopting different distributions for their position in the Galaxy, intrinsic physical properties, pair emission models, in order to overcome the incompleteness of the ATNF catalogue. We fit the e
+ AMS-02 data together with a secondary component due to collisions of primary cosmic rays with the interstellar medium. We find that several mock galaxies have a pulsar population able to explain the observed e+ flux, typically by few, bright sources. We determine the physical parameters of the pulsars dominating the e
+ flux, and assess the impact of different assumptions on radial distributions, spin-down properties, Galactic propagation scenarios and e
+ emission time.
Searching for High-Energy Neutrinos from Ultra-Luminous Infrared Galaxies with IceCube
Authors: Correa Pablo
Published: February 2022

This work presents an IceCube search for high-energy neutrinos from Ultra-Luminous Infrared Galaxies (ULIRGs). ULIRGs are the most luminous infrared objects in the sky, with infrared luminosities exceeding 1012 solar luminosities. They are mainly powered by starbursts that exhibit star-formation rates larger than 100 solar masses per year. In addition, an active galactic nucleus (AGN) can also contribute significantly to the ULIRG luminosity output. The acceleration of hadrons, and consequently the production of neutrinos, can occur both in starburst and AGN environments. As such, ULIRGs form a source population that could be responsible for a significant fraction of the diffuse neutrino flux observed by IceCube. In this study we perform a stacking analysis on a representative sample of 75 ULIRGs with redshift z ≤ 0.13 using 7.5 years of IceCube data. We find no evidence for astrophysical neutrinos correlated with our selection of ULIRGs. We therefore compute upper limits on the contribution of the ULIRG source population to the diffuse neutrino observations, and also use these limits to constrain model predictions.
Update on the characterisation of the pGCT, a prototype of 4m dual-mirror Cherenkov Telescope
Authors: Rebert E. , Dournaux J.L. , Fasola G. , Horville D. , Sol H. , Amans J.P. , de Frondat F. , Huet J.M. , Laporte P. , Zech A.
Published: February 2022

The Gamma-ray Cherenkov Telescope prototype (pGCT) is a prototype of an Imaging Atmospheric Cherenkov Telescope, developed as Small-Sized Telescope (SST) of 4m during the preparation of the Cherenkov Telescope Array (CTA). Based on a Schwarzschild-Couder dual-mirror optical design aiming to provide an optimised Point Spread Function (PSF) on a wide field, it had its first Cherenkov light on the Meudon site of the Observatoire de Paris in 2015. Since the decision of CTA to harmonize its future SSTs, the pGCT instrument and the experience gained with its development are now used by the Observatoire de Paris team to provide a test bench for Cherenkov astronomy and a pedagogical tool for educational purposes in Meudon. This paper briefly describes the design of the pGCT and presents the latest advances in the optics of the prototype and its characterisation, directly related to the implementation of new high-quality metallic mirrors carried out since 2020.
Dense neutrino oscillations : beyond two flavor
Authors: Chakraborty Madhurima
Published: February 2022

In a dense supernova environment, neutrinos can undergo flavor conversions known as the collective oscillations. These self induced neutrino flavor conversions (collective oscillations) are almost exclusively studied in the standard two flavor scenario. We study these oscillations in the complete three flavor scenario. The ‘fast’ conversions are fascinating distinctions of the dense neutrino systems. In the fast modes the collective oscillation dynamics are independent of the neutrino mass, growing at the scale of the large neutrino-neutrino interaction strength (105 km−1 ) of the dense core. This is extremely fast, as compared to the usual ‘slow’ collective modes driven by much smaller vacuum oscillation frequencies (100 km−1). We perform the first non-linear simulations of fast conversions in the presence of three neutrino flavors which is motivated from the recent supernova simulations with muon production. We relax the standard

ν

μ
,
τ

=

ν
¯

μ
,
τ

(two-flavor) assumption. Our results show the significance of muon and tau lepton number angular distributions, together with the traditional electron lepton number ones and thus explain the need for a complete three flavor analysis.
JUNO Non-oscillation Physics
Authors: Settanta Giulio
Published: February 2022

The JUNO observatory, a 20 kt liquid scintillator detector to be completed in 2021 in China, belongs to the next-generation of neutrino detectors, which share the common features of having a multi-ton scale and an energy resolution at unprecedented levels. Beside the ambitious goal of neutrino mass ordering determination, the JUNO Collaboration plans also to perform a wide series of other measurements in the neutrino and astroparticle fields, rare processes and searches for new physics. The detector characteristics will allow the detection of neutrinos from many sources, like supernovae, the Sun, atmospheric and geoneutrinos. Other potential studies accessible to JUNO include the search for exotic processes, such as nucleon decays, Dark Matter and magnetic monopoles interactions, light sterile neutrinos production. This work reviews the physics potential of JUNO about non-reactor neutrino sources, highlighting the unique contributions that the experiment will give to the various fields in the forthcoming years.
Low-energy reactor neutrino physics with the CONNIE experiment
Authors: Nasteva Irina
Published: February 2022

The Coherent Neutrino-Nucleus Interaction Experiment (CONNIE) uses fully depleted high-resistivity CCDs (charge coupled devices) with the aim of detecting the coherent elastic scattering of reactor antineutrinos off silicon nuclei and probing physics beyond the Standard Model. The analysis of the 2016‖2018 data allowed us to set an upper limit at 95% confidence level on the coherent scattering rate, which was used to place stringent constraints on simplified extensions of the Standard Model with light scalar and vector mediators. In 2019, the experiment operated with an improved readout and a lower energy threshold of 50 eV. We present the performance of the CONNIE experiment, new results of the analysis of 2019 data, and the recent update of the detector with skipper CCDs.
Direct measurement of topological information for Cherenkov lights using HUNI-ZICOS detector
Authors: Yoshiyuki Fukuda , Shigetaka Moriyama , Katsuki Hiraide , Izumi Ogawa , Takahiro Gunji , Ryohei Hayami , Satoru Tsukada , Shunsuke Kurosawa
Published: February 2022

The topological information of Cherenkov light emitted from low energy electron was directly measured by HUNI-ZICOS detector. A 1.484 MeV electron with fixed direction to the center of hemispherical surface of the detector was generated by Compton back scattering with 100 degree from 88Y 1.836 MeV gamma. The observed averaged angle of Cherenkov light emitted from this electron was clustered around 40 degree assuming the vertex position to be at the center of truncated icosahedron photomultiplier jig. It was not Cherenkov angle around 47 degree as obtained by old simulation and the vertex to be the center of light yield for hitted photomultiplier. According to the HUNI-ZICOS simulation, the averaged angle of Cherenkov light was also clustered around 40 degree. On the other hands, the simulated averaged angle of scintillation was clustered around 49 degree, which is consistent with the averaged value of angle between the direction to center of hemisphere surface and each photomultiplier from the center of the jig. The obtained hitmap seemed to have same non flat structure as that of simulation due to Cherenkov ring. This is an evidence that Cherenkov lights emitted from 1.484 MeV electron should really have their topology. Therefore, we concluded that we will be able to reduce 208Tl background using the averaged angle for 96 Zr neutrinoless double beta decay search.
GERDA: Final Results and Physics Beyond Neutrinoless Double-Beta Decay
Authors: Krause P.
Published: February 2022

The GERDA experiment searched for the lepton number violating neutrinoless double-beta 0υββ decay of 76 Ge. Observation of this decay would provide answers to fundamental problems in particle physics and cosmology, including the origin of neutrino masses and baryon asymmetry in the universe. The GERDA experiment achieved the most stringent lower limit on the half-life of the 0υββ decay of 1.8 • 1026 yr at 90% C.L. (which coincides with the sensitivity) by operating high-purity germanium (HPGe) detectors enriched in 76Ge submerged in liquid argon (LAr). The collaboration could achieve this breakthrough by reducing the background event rate to 5.2 • 10–4 counts/(keV kg yr) at the end-point energy. This unprecedented background index could be achieved by developing unique technologies like utilizing the scintillation light of the LAr to reject efficiently background events that deposit energy simultaneously in the HPGe detectors and in LAr, and the pulse shape discrimination which exploits specific event topologies of backgrounds and signal candidates. Due to the ultra-low background approach the GERDA data is also suited for other rare event searches beyond the 0υββ decay like the search for super-WIMPs.
Neutrino NSI effects on future solar sector measurements
Authors: Molina Sedgwick S , Martínez-Miravé P , Tórtola M
Published: February 2022

The next-generation experiment JUNO will determine the solar oscillation parameters - sin2
θ
12 and

Δ

m

21

2

- with great accuracy, in addition to measuring sin2
θ
13,

Δ

m

31

2

and the mass ordering. In parallel, the continued study of solar neutrinos at Hyper-Kamiokande will provide complementary measurements in the solar sector. Here we address the expected sensitivity to non-universal and flavour-changing non-standard interactions (NSI) with d-type quarks from the combination of these two future neutrino experiments. We also show the robustness of the measurement of the solar parameters and sin2
θ
12 and

Δ

m

21

2

in the presence of NSI and comment on the enduring potential viability of the LMA-D solution.
Revealing the Majorana nature of neutrinos through a precision measurement of the CP phase
Authors: Carrasco-Martínez J.C. , Díaz F.N. , Gago A.M.
Published: February 2022

We show that it is possible to reveal the nature of neutrino by measuring the Majorana phase at the DUNE experiment. The Majorana phase is activated in the neutrino oscillation framework due to the introduction of a decoherence environment. Being that depending on the value of the Majorana phase and the intensity of decoherence, the measurement of the Dirac CP violation phase δCP can be highly spoiled. We will notice the latter by comparing the measurements of the CP phases that will take place in DUNE and T2HK. Finally, we will also assess the possibility of the measurement itself of the Majorana phase at DUNE.
Search for exotic neutrino-electron interactions using solar neutrinos in XMASS-I
Authors: Ogawa Hiroshi
Published: February 2022

In recent years, the larger size and lower background of dark matter search detectors have opened up a new frontier of searching for new physics other than dark matter using these detectors. One of them is the search for new properties of neutrinos by observing the interaction of neutrinos at low energy. XMASS is a multi-purpose experiment using xenon exclusively in ites liquid xenon (LXe) and is located at the Kamioka Observatory in Japan. We searched for exotic neutrino-electron interactions that could be produced by either a neutrino millicharge, a neutrino magnetic moment, or by dark photons, which might affect the intearction cross section of solar neutrinos in XMASS. We analyzed data taken between November 2013 and March 2016 amounting to 711 live days. No significant signal has been found above the predicted background level in detector. We obtained an upper limit for neutrino millicharge of 5.4 × 10–11e for all flavors of neutrino. We also set individual flavors limits for υμ and ν
τ, which are the best limits obtained by direct detection. We also obtain an upper limit for the neutrino magnetic moment of 1.8× 10–10μ
B
. In addition, we obtain upper limits for the coupling constant of dark photons in the U(1)
B–L
model. This result almost excludes the possibility to understand the muon g — 2 anomaly by dark photons.
Spectroscopy of geoneutrinos with Borexino
Authors: Kumaran Sindhujha
Published: February 2022

Borexino is a 280-ton liquid scintillator detector located at the Laboratori Nazionali del Gran Sasso (LNGS), Italy and is one of the two detectors that has measured geoneutrinos so far. The unprecedented radio-purity of the scintillator, the shielding with highly purified water, and the placement of the detector at 3800 m w.e. depth have resulted in very low background levels, making Borexino an excellent apparatus for geoneutrino measurements. This article will summarize the recent geoneutrino analysis and results with Borexino, from the period December 2007 to April 2019. The updated statistics and the optimized analysis techniques such as an increased fiducial volume and sophisticated cosmogenic vetoes, have led to more than a two-fold increase in exposure when compared to the previous measurement in 2015, resulting in a significant improvement in the precision. In addition, Borexino has also been able to reject the null hypothesis of the mantle geoneutrino signal with 99% C.L., for the first time, by exploiting the extensive knowledge of the crust surrounding the detector. This article will also include other geological interpretations of the obtained results such as the calculation of the radiogenic heat and the comparison of the results to various predictions. Additionally, upper limits for a hypothetical georeactor that might be present at different locations inside the Earth will also be discussed.
Status of the Short-Baseline Near Detector at Fermilab
Authors: Crespo-Anadón J.I.
Published: February 2022

The Short-Baseline Near Detector (SBND) will be one of three liquid argon time projection chamber neutrino detectors positioned along the axis of the Booster Neutrino Beam at Fermilab, as part of the Short-Baseline Neutrino (SBN) Program. The detector is currently in the construction phase and is anticipated to begin operation in the second half of 2022. SBND is characterized by superb imaging capabilities and will record over a million neutrino interactions per year. Thanks to its unique combination of measurement resolution and statistics, SBND will carry out a rich program of neutrino interaction measurements and novel searches for physics beyond the Standard Model. It will enable the potential of the overall SBN sterile neutrino program by performing a precise characterization of the unoscillated event rate, and by constraining BNB flux and neutrino-argon cross-section systematic uncertainties.
The Selena Neutrino Experiment
Authors: Chavarria A.E.
Published: February 2022

Imaging sensors made from an ionization target layer of amorphous selenium (aSe) coupled to a silicon complementary metal-oxide-semiconductor (CMOS) active pixel array for charge readout are a promising technology for neutrino physics. The high spatial resolution in a solid-state target provides unparalleled rejection of backgrounds from natural radioactivity in the search for neutrinoless ββ decay and for solar neutrino spectroscopy with 82Se. We present results on the ionization response of aSe measured from the photoabsorption of 122 keV γ rays in a single-pixel device. We report on the progress in the fabrication and testing of the first prototype imaging sensors based on the Topmetal II
− pixelated CMOS charge readout chip. We explore the scientific reach of a large neutrino detector with the proposed technology based on our experimental understanding of the sensor performance.
The neutrinoless double beta decay CROSS experiment: demonstrator with surface sensitive bolometers
Authors: Zolotarova A. , Bandac I.C. , Barabash A.S. , Berest V. , Bergé L. , Bourgeois Ch. , Calvo-Mozota J.M. , Carniti P. , Chapellier M. , de Combarieu M. , Dafinei I. , Danevich F.A. , Dumoulin L. , Ferri F. , Giuliani A. , Gotti C. , Ph. Gras , Guerard E. , Ianni A. , Khalife H. , Konovalov S.I. , Loaiza P. , Madhukuttan M. , de Marcillac P. , Mariam R. , Marnieros S. , Marrache-Kikuchi C.A. , Martinez M. , Nones C. , Olivieri E. , Pessina G. , Poda D.V. , Redon Th. , Scarpaci J.-A. , Tretyak V.I. , Umatov V.I. , Zarytskyy M.M.
Published: February 2022

The CROSS experiment is proposing to use a new technology of surface sensitive bolometers for low-background neutrinoless double beta decay searches. Efficient rejection of surface α and β events will allow to reach background in the region of interest below than 10−4 cnts/keV/kg/yr. The isotopes of interest, which are 130Te and 100Mo, are investigated with TeO2 and Li2MoO4 bolometers. The surface sensitivity is achieved thanks to the evaporation of thin metallic film on the crystal surface that modifies the pulse shape of near-surface events. An investigation of various pulse shape parameters was performed. The analysis shows that one of the best parameters for discrimination is the integrated area of the raw signal both for TeO2 and Li2MoO4 with Pd-Al (10 nm - 100 nm) bi-layer.
Violation of Equivalence Principle at IceCube
Authors: Fiorillo Damiano F. G.
Published: February 2022

We study the effects of a Violation of Equivalence Principle (VEP) on neutrino oscillations. We analyze the IceCube data on atmospheric neutrino fluxes to obtain updated constraints on the parameter space of VEP, with the benchmark choice that neutrinos with different masses couple with different strengths to the gravitational field. We find that the VEP parameters times the local gravitational potential at Earth can be constrained at the level of 10−27. The constraints from atmospheric neutrinos strongly depend on the assumption that the neutrino eigenstates interacting diagonally with the gravitational field coincide with the mass eigenstates, which is not a priori justified: as an example, if the basis of diagonal gravitational interaction coincide with the flavor basis, atmospheric neutrinos cannot constrain the model. Finally, we quantitatively study the effect of a VEP on the flavor composition of the astrophysical neutrinos, stressing again the interplay with the basis in which the VEP is diagonal: we find that some choices of such basis are already in tension with the flavor ratio of the diffuse neutrino flux measured by IceCube.
IPPOG Global Cosmic Rays Portal: Making Cosmic Rays Studies available to schools worldwide
Authors: Gulejova Barbora Bruant
Published: February 2022

The International Particle Physics Group (IPPOG) is a global network active in informal education and outreach in particle physics and related research, including cosmic-ray and astro-particle physics. Since many years, IPPOG has been actively supporting the International Cosmic Day organized by DESY and the International Muon Week organized by Quarknet. In 2015 IPPOG started work on establishing a universal portal through which successful cosmic-ray study programmes can reach out to teachers and students around the world. This common web platform is being developed by IPPOG in the frame of its new IPPOG web pages. It will contain all information for schools interested in taking part in cosmic-ray experiments and analysing real data in classroom; also instructions about how to build, borrow, or purchase cosmic-ray detectors. The platform will also facilitate collaboration and exchanges between the experiments’ project managers and advertising of related events.
Annual modulations of the angular recoil—flux/energy distributions of WIMP—scattered target nuclei observed at an underground laboratory
Authors: Shan Chung-Lin
Published: February 2022

In this article, we demonstrate the target and WIMP–mass dependent “annual modulations” of the angular distributions of the recoil flux and energy of WIMP–scattered target nuclei observed at the Laboratorio Subterráneo de Canfranc (LSC). For readers’ reference, simulation plots with different WIMP masses and frequently used target nuclei for all functionable underground laboratories can be found and downloaded on our online (interactive) demonstration webpage (http://www.tir.tw/phys/hep/dm/amidas-2d/).
Background model of the ANAIS-112 dark matter experiment
Authors: Amaré J , Cebrián S , Cintas D , Coarasa I , García E , Martínez M , Oliván M A , Ortigoza Y , Ortiz de Solórzano A , Puimedón J , Salinas A , Sarsa M L , Villar P
Published: February 2022

The ANAIS (Annual modulation with NaI(Tl) Scintillators) experiment aims at the confirmation or refutation of the DAMA/LIBRA positive annual modulation signal in the low energy detection rate. ANAIS-112, consisting of nine 12.5 kg NaI(Tl) modules, is taking data since August, 2017 at the Canfranc Underground Laboratory (LSC) in Spain. Results from the analysis of three years of data are compatible with the absence of modulation. The background model developed for all nine ANAIS-112 detectors was established from commissioning data and non-blinded events in the first year of data taking. Now, background characterization is being improved profiting from the larger accumulated exposure available. Here, the background model is described and comparisons of model and measurements for energy spectra and counting rate time evolution for three-year exposure (considering different analysis conditions) are presented.
Collective neutrino oscillations in moving and polarized matter
Authors: Chen Zekun , Kouzakov Konstantin , Li Yu-Feng , Shakhov Vadim , Stankevich Konstantin , Studenikin Alexander
Published: February 2022

We consider neutrino evolution master equations in dense moving and polarized matter consisted of electrons, neutrons, protons and neutrinos. We also take into account the neutrino magnetic moment interaction with a magnetic field. We point out the mechanisms responsible for the neutrino spin precession and provide the expressions for the corresponding interaction Hamiltonians that should be taken into account in theoretical treatments of collective neutrino oscillations.
Event reconstruction performance with new retro-reflector based designs for water Cherenkov detectors
Authors: Berns L , Fujigami S , Kuze M , Yamaguchi Y
Published: February 2022

We have proposed the possibility of a cost-efficient way to improve the detector performance for water Cherenkov detectors, by reflecting the usually lost light falling between photo-detectors onto the other side of the tank with retro-reflectors. Using a detector simulation based on optical measurements of retro-reflectors, we developed a convolutional neural network-based reconstruction algorithm. Here we report on the reconstruction performance for ring events in the energy scale expected for atmospheric and accelerator neutrinos under various candidate detector configurations.
Optimizing the time resolution of cryogenic calorimeters with NTDs: the CALIPSO project
Authors: Nutini Irene
Published: February 2022

The CALIPSO project deals with the development and optimization of low temperature (∼10 mK) solid state detectors. The goal of the project is to propose new strategies for improving the time resolution of cryogenic scintillating calorimeters, read with NTD thermistors. We will test new NTD-detector coupling techniques and optimize the NTD operation to make the response faster. In parallel, we will work on improving the scintillation light yield for different crystals at low temperatures. Rare events physics experiments utilizing the NTD-detector technology on a large scale, such as the ones searching for the neutrinoless double beta decay (CUORE, CUPID), could profit from the results of this project.
Primordial Black Holes and Scotogenic dark matter
Authors: Kitabayashi Teruyuki
Published: February 2022

We study the correlations between the initial density of primordial black holes and the lepton flavor violating μ → eγ process via scotogenic dark matter. The initial density of PBHs may be constrained with the future MEG II experiment.
Xenon doping of Liquid Argon in ProtoDUNE Single Phase: first results
Authors: Gallice Niccolò
Published: February 2022

Doping Liquid Argon (LAr) with xenon is a known technique to shift the light emitted by argon (128 nm) to a longer wavelength to ease its detection. The largest Xenon doping test ever performed in a LArTPC was carried out in ProtoDUNE Single Phase (ProtoDUNE-SP) at the CERN Neutrino Platform. The response of such a large TPC (7701 of Liquid Argon and 4401 of fiducial mass) has been studied using the ProtoDUNE Photon Detection System (PDS) and a dedicated setup installed before the run. With the first, it was possible to study the light detected in the system as a function of the xenon concentration and to characterise the light collection efficiency with respect to the track position. With the second system it was possible to disentangle the LAr (128 nm) light from the xenon (178 nm) light using two dedicated X-ARAPUCA modules. The run was fully satisfactory, it was possible to measure directly the increase of the xenon light component during doping; furthermore most of the LAr light quenched by impurities was fully recovered even at small Xenon concentration (< 20 ppm in mass). A study of the collected scintillation light as a function of the track position showed an improvement of the detector response uniformity.
Data analysis strategy used for the detection of CNO solar neutrinos with Borexino
Authors: Pelicci L
Published: February 2022

Borexino is a large liquid scintillator experiment located at the underground INFN Laboratori Nazionali del Gran Sasso, in Italy. It was designed and built with the primary goal of real-time detection of low energy solar neutrinos, and in more than ten years of data taking it has measured all the neutrino fluxes produced in the proton-proton chain, i.e. the main fusion process accounting for 99% of the energy production in the Sun. Recently, after improvements and developments in both hardware and software, Borexino has provided the first observation of solar neutrinos emitted from the subdominant Carbon-Nitrogen-Oxygen (CNO) fusion cycle. All the crucial steps of the analysis strategy adopted to disentangle the signal of CNO neutrinos from backgrounds present in the detector will be described in this article.
Advances on the performance and fabrication of low-background PTFE based electronic substrates by surface modification
Authors: Zhang S J , Liu Y Y , Cheng J P , Lv S S
Published: February 2022

The weak signal from rare event is readily submerged in the background and thus results in substantial challenges in its detection, which spurs researchers to decrease the surroundings background of detectors as low as possible. To this end, a low-background non-adhesive polytetrafluoroethylene (PTFE) flexible copper-clad laminate (PTFE-FCCL) was prepared by surface treatment. Specifically, the PTFE substrate was processed by ion implantation and the transition layer deposition; the adhesion between PTFE and copper of PTFE-FCCL is found to remain stable after barely immersing in liquid nitrogen. Furthermore, the surface morphology and the dielectric properties of the substrate were characterized and tested. The results presented herein offer a novel method to fabricate electronic substrates that can facilitate rare event detection.
Purity monitoring for ProtoDUNE-SP
Authors: Xiao Yiwen
Published: February 2022

The Deep Underground Neutrino Experiment is a next-generation long-baseline neutrino oscillation experiment based on liquid argon time projection chamber technology. DUNE-s single-phase prototype ProtoDUNE-SP at CERN finished its two-year Phase-1 running in July 2021, successfully collected test-beam and cosmic ray data. A key aspect of LArTPC calibration is the lifetime of drift electrons. A purity monitor is a miniature TPC measuring the lifetime of electrons generated from the photocathode via the photoelectric effect. It enables continuous monitoring of the detector status, especially when filling the cryostat and when liquid argon recirculation systems operate. The purity monitoring system in ProtoDUNE-SP Phase-1 monitored liquid argon purity throughout its entire lifetime. It is essential to the experiment’s successful commissioning, operation, and data taking. This poster discusses the design, implementation, and results of purity monitors and plans.
Influence of NaI background and mass on testing the DAMA modulation
Authors: Zurowski Madeleine J. , Barberio Elisabetta
Published: February 2022

NaI experiments should be sensitive to the same DM-SM interactions proposed to explain the observed DAMA modulation. As such, they are often called a ‘model independent’ test of the signal. While the same signal will be produced at all NaI detectors, the ability to observe it is strongly dependent on the experimental set up - in particular the mass and background of the target. We present here a study on how changes to these values influence the ability of a detector to observe a characteristic DM modulation. We consider both the standard elastic, spin independent WIMP and a model independent analysis assuming exactly the modulation signal observed by DAMA (i.e., making no assumptions about the particle interaction model producing this signal), and find that in both cases a lower background is favoured over a higher exposure mass (based on currently achievable levels).
The cosmic muon-induced background for the LEGEND-1000 alternative site at LNGS
Authors: Neuberger M , Pertoldi L. , Schönert S , Wiesinger C.
Published: February 2022

The in-situ production of long-lived radio-isotopes by cosmic muon interactions may generate a non-negligible background for rare event searches in the deep subsurface. The delayed decay of 77(m)Ge has been identified as the dominant in-situ cosmogenic contributor for a neutrinoless double-beta decay search with 76Ge. The future ton-scale LEGEND-1000 experiment requires a total background of ≤ 10−5 cts/(keV-kg-yr). Dedicated Monte Carlo studies of the 77(m)Ge background at the alternative LNGS site were performed. The addition of passive neutron moderators, in combination with a delayed coincidence strategy, results in a background contribution of 8.6 × 10−7 cts/(keV.kg.yr) with an additional dead time of < 9%.
Comparative study of Dirac and Majorana ultrahigh-energy neutrino oscillations in an interstellar magnetic field
Authors: Abeyadira Daniil , Kouzakov Konstantin , Studenikin Alexander
Published: February 2022

We examine the ultrahigh-energy neutrino propagation in interstellar space in the Dirac and Majorana cases. Employing the two-neutrino mixing approximation and using the astrophysical constraints on neutrino magnetic moments, we show that both the flavor and the spin oscillations of the Dirac and Majorana neutrinos exhibit qualitatively different behaviors in an interstellar magnetic field for neutrino-energy values characteristic of, respectively, the cosmogenic neutrinos and well above the Greisen-Zatsepin-Kuz’min cutoff.
Core-collapse simulation of SN 1987A binary progenitor and its multimessenger signals
Authors: Nakamura Ko
Published: February 2022

We perform a three-dimensional self-consistent core-collapse supernova simulation using a binary evolution progenitor model of SN 1987A. This progenitor model is based on a slow-merger of 14 M∹ and 9 M∹ stars and it satisfies most of the observational constraints such as red-to-blue evolution, lifetime, total mass and position in the Hertzsprung-Russell diagram at collapse, and chemical anomalies. We find that this progenitor model successfully present explosion and leave a 1.53 M∹ neutron star with a kick velocity of 70kms−1 and a spin period of 0.1 s. Assuming a detector sensitivity of Kamiokande-II and the distance to the supernova of 51 kpc, we obtain 16 neutrino detection events in one second. Some characteristic modes in its gravitational wave signal are also discussed in this article.
Neutral bremsstrahlung in TPCs
Authors: Amedo P. , González-Díaz D. , Jones B.J.P.
Published: February 2022

Traditionally, it has been assumed that electroluminescence (EL) in time projection chambers was purely an excimer-based emission. This idea changed when neutral bremsstrahlung (NBrS) was observed first in argon and subsequently in xenon a few years ago. In this work we explore further the framework used to explain these observations, presenting results for noble gas-based mixtures, as well as mixtures including small fractions of a molecular additive (‘quencher’). Spectral content and yields are discussed in some cases of contemporary interest, together with their pressure-scalings.
EIC detector overview
Authors: Higinbotham D.W.
Published: February 2022

The Electron Ion Collider will have two interaction regions that can be instrumented with detectors. The first region will be instrumented as part of the project and needs to be capable of delivering the physics that has been outlined by the National Academy of Sciences and ready at the start of beam commissioning near the end of this decade. Plans for a second complementary detector to be located at a second interaction region are already in progress and will hopefully come to fruition just few years after the first detector comes online. While the basic parameters of these detectors are being selected using conventional approaches, the optimization of the detectors is already being enhanced by making use of advanced optimization techniques.