cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A laboratory investigation of thermally induced pore pressures in the Callovo-Oxfordian Claystone
Creators: name: Mohajerani, Mehrdokht
name: Delage, Pierre
name: Sulem, Jean
name: Monfared, Mohammad
name: Tang, Anh-Minh
name: Gatmiri, Behrouz
Publisher: name: arXiv
Year: 2013
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: In the framework of research into radioactive waste disposal, it was decided to investigate the thermally induce pore pressure occurring in the Callovo-Oxfordian claystone, a possible host rock in which the ANDRA underground laboratory of Bure (East of France) has been excavated. Thermal pore pressures appear in low permeability soils and rocks because the thermal expansion coefficient of water is significantly higher than that of the solid grains (Campanella and Mitchell; 1968 [1], Ghabezloo and Sulem; 2009 [2]). This phenomenon has clearly been observed in various in-situ heating tests conducted in Opalinus claystone in the Mont-Terri Underground Research Laboratory (URL) in Switzerland (HE-D test) and in Callovo-Oxfordian (COx) claystone in the Bure URL in France (TER test, Wileveau and Su; 2007 [3]) The processes of coring, transportation, storage and specimen trimming induce some desaturation in the sample. Due to the very low permeability (10-20 m2) of the COx claystone, a long period of time is necessary to properly resaturate the sample, a mandatory condition to satisfactorily investigate thermal pressurisation. Particular emphasis was hence put on the previous saturation procedure that was carried out under in-situ effective stress condition. Thermal pressurization has been investigated by performing undrained heating tests while measuring pore pressures changes in a specially adapted thermal isotropic compression cell. Special care was devoted to calibration procedures to account for the effects of the system on the pore pressure measurements. The thermal pressurization coefficient measured appeared to change with temperature, mainly because of the changes with temperature of both the water thermal expansion coefficient of water and the drained compression coefficient of the claystone.
Segmented Vortex Telescope and its Tolerance to Diffraction Effects and Primary Aberrations
Creators: name: Treviño, Juan P.
name: López-Cruz, Omar
name: Chávez-Cerda, Sabino
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We propose the segmented Large Millimeter Telescope (LMT/GTM),as the largest spatial light modulator capable of producing vortex beams of integer topological charge. This observing mode could be applied for direct exoplanet searches in the millimeter or submillimeter regimes. We studied the stability of the vortex structure against aberrations and diffraction effects inherent to the size and segmented nature of the collector mirror. In the presence of low order aberrations the focal distribution of the system remains stable. Our results show that these effects depend on the topological charge of the vortex and the relative orientation of the aberration with respect to the antenna axis. Coma and defocus show no large effects in the image at the focal plane, nevertheless the system is very sensitive to astigmatism. Heat turbulence, simulated by random aberrations, shows that the system behaves in a similar way as astigmatism dissociating the vortices. We propose the Segmented Vortex Telescope as a novel approach for the detection of giant planets outside circumstellar disks around nearby stars. Since our results are applicable to other facilities with segmented surfaces, we suggest that this idea should be considered as a regular observation mode complementary to interferometric methods.
description: To appear at the August 2013 feature issue of Optical Enginering: Ground-Based/Airborne Telescopes and Instrumentation. Includes 11 figures
Covariant Differential Identities and Conservation Laws in Metric-Torsion Theories of Gravitation. I. General Consideration
Creators: name: Lompay, Robert R.
name: Petrov, Alexander N.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 83D05

description: Arbitrary diffeomorphically invariant metric-torsion theories of gravity are considered. It is assumed that Lagrangians of such theories contain derivatives of field variables (tensor densities of arbitrary ranks and weights) up to a second order only. The generalized Klein-Noether methods for constructing manifestly covariant identities and conserved quantities are developed. Manifestly covariant expressions are constructed without including auxiliary structures like a background metric. In the Riemann-Cartan space, the following \emph{manifestly generally covariant results} are presented: (a) The complete generalized system of differential identities (the Klein-Noether identities) is obtained. (b) The generalized currents of three types depending on an arbitrary vector field displacements are constructed: they are the canonical Noether current, symmetrized Belinfante current and identically conserved Hilbert-Bergmann current. In particular, it is stated that the symmetrized Belinfante current does not depend on divergences in the Lagrangian. (c) The generalized boundary Klein theorem (third Noether theorem) is proved. (d) The construction of the generalized superpotential is presented in details, and questions related to its ambiguities are analyzed.
description: 23 pages, 0 figures, revtex 4.1
Observational Constraints of Modified Chaplygin Gas in RS II Brane
Creators: name: Ranjit, Chayan
name: Rudra, Prabir
name: Kundu, Sujata
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: FRW universe in RS II braneworld model filled with a combination of dark matter and dark energy in the form of modified Chaplygin gas (MCG) is considered. It is known that the equation of state (EoS) for MCG is a three-variable equation determined by $A$, $α$ and $B$. The permitted values of these parameters are determined by the recent astrophysical and cosmological observational data. Here we present the Hubble parameter in terms of the observable parameters $Ω_{m0}$, $Ω_{x0}$, $H_{0}$, redshift $z$ and other parameters like $A$, $B$, $C$ and $α$. From Stern data set (12 points), we have obtained the bounds of the arbitrary parameters by minimizing the $χ^{2}$ test. The best-fit values of the parameters are obtained by 66%, 90% and 99% confidence levels. Next due to joint analysis with BAO and CMB observations, we have also obtained the bounds of the parameters ($B,C$) by fixing some other parameters $α$ and $A$. The best fit value of distance modulus $μ(z)$ is obtained for the MCG model in RS II brane, and it is concluded that our model is perfectly consistent with the union2 sample data.
description: 21 pages, 10 figures. arXiv admin note: substantial text overlap with arXiv:1206.0507, arXiv:1304.1281, arXiv:1211.2785, arXiv:1211.2783
Strain and band-mixing effects on the excitonic Aharonov-Bohm effect in In(Ga)As/GaAs ringlike quantum dots
Creators: name: Arsoski, Vladimir V.
name: Tadić, Milan Ž.
name: Peeters, François M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Neutral excitons in strained axially symmetric In(Ga)As/GaAs quantum dots with ringlike shape are investigated. Similar to experimental self-assembled quantum rings, the analyzed quantum dots have volcano-like shapes. The continuum mechanical model is employed to determine the strain distribution, and the single-band envelope function approach is adopted to compute the electron states. The hole states are determined by the axially symmetric multiband Luttinger-Kohn Hamiltonian, and the exciton states are obtained from an exact diagonalization. We found that the presence of the inner layer covering the ring opening enhances the excitonic Aharonov-Bohm (AB) oscillations. The reason is that the hole becomes mainly localized in the inner part of the quantum dot due to strain, whereas the electron resides mainly inside the ring-shaped rim. Interestingly, larger AB oscillations are found in the analyzed quantum dot than in a fully opened quantum ring of the same width. Comparison with the unstrained ring-like quantum dot shows that the amplitude of the excitonic Aharonov-Bohm oscillations are almost doubled in the presence of strain. The computed oscillations of the exciton energy levels are comparable in magnitude to the oscillations measured in recent experiments.
description: 16 pages, 9 figures, accepted for publication in Physical Review B
Shaping the relation between the mass of supermassive black holes and the velocity dispersion of galactic bulges
Creators: name: Chan, Man Ho
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: I use the fact that the radiation emitted by the accretion disk of supermassive black hole can heat up the surrounding gas in the protogalaxy to achieve hydrostatic equilibrium during the galaxy formation. The correlation between the black hole mass M_BH and velocity dispersion σthus naturally arises. The result generally agrees with empirical fittings from observational data, even with M_BH \leq 10^6M_sun. This model provides a clear picture on how the properties of the galactic supermassive black holes are connected with the kinetic properties of the galactic bulges.
description: 8 pages, 1 figure, accepted by Astrophysics and Space Science
title: Experiments on Charitable Giving: Study of the impact of restricted choice and imperfect informaion on warm glow givers
Creators: name: Mirza, Zarak
Publisher: name: University of Kent
Year: 2017

description: In some instances, charities insist on donors giving more than some fixed, minimum amount. In many other instances, charities frame appeals for funds in a way that suggests there is a minimum desirable donation. So, what are the effects on charitable giving if a minimum donation is required? We first provide a simple theoretical model that shows the effects are ambiguous. Some people are predicted to give more to the charity, some less and the overall effect could go either way. We then report the results of two lab experiments. In both experiments we find that giving is significantly lower when a minimum donation is required. Our two experiments consider very different settings. The first experiment involves individual decision making with large opportunity costs of giving. The second involves group involvement with direct incentives to give. That we observe lower giving in both settings suggests that imposing a minimum donation may not be an effective way to increase giving. We also explore the dynamic nature of giving under restrictive conditions along with the impact of screening and signalling on giving behaviour.
High sensitivity measurements of thermal properties of textile fabrics
Creators: name: Romeli, D.
name: Barigozzi, G.
name: Esposito, S.
name: Rosace, G.
name: Salesi, G.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A new testing apparatus is proposed to measure the thermal properties of fabrics made from polymeric materials. The calibration of the apparatus and the data acquisition procedure are considered in detail in order to measure thermal conductivity, resistance, absorption and diffusivity constants of the tested fabric samples. Differences between dry and wet fabrics have been carefully detected and analyzed. We have developed a new measurement protocol, the "ThermoTex" protocol, which agrees with the UNI EN 31092 standard and entails an accurate quantification of the experimental errors according to a standard statistical analysis, thus allowing a rigorous investigation of the physical behavior of the phenomena involved. As a consequence, our machinery exhibits great potentialities for optimizing the thermal comfort of fabrics, according to the market demand, thanks to the possible development of a predictive phenomenological theory of the effects involved.
description: RevTeX4 source file; 9 pages, 9 figures
Optimal non-linear transformations for large scale structure statistics
Creators: name: Carron, Julien
name: Szapudi, Istvan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Recently, several studies proposed non-linear transformations, such as a logarithmic or Gaussianization transformation, as efficient tools to recapture information about the (Gaussian) initial conditions. During non-linear evolution, part of the cosmologically relevant information leaks out from the second moment of the distribution. This information is accessible only through complex higher order moments or, in the worst case, becomes inaccessible to the hierarchy. The focus of this work is to investigate these transformations in the framework of Fisher information using cosmological perturbation theory of the matter field with Gaussian initial conditions. We show that at each order in perturbation theory, there is a polynomial of corresponding order exhausting the information on a given parameter. This polynomial can be interpreted as the Taylor expansion of the maximally efficient "sufficient" observable in the non-linear regime. We determine explicitly this maximally efficient observable for local transformations. Remarkably, this optimal transform is essentially the simple power transform with an exponent related to the slope of the power spectrum; when this is -1, it is indistinguishable from the logarithmic transform. This transform Gaussianizes the distribution, and recovers the linear density contrast. Thus a direct connection is revealed between undoing of the non-linear dynamics and the efficient capture of Fisher information. Our analytical results were compared with measurements from the Millennium Simulation density field. We found that our transforms remain very close to optimal even in the deeply non-linear regime with σ^2 \sim 10.
description: 11 pages, matches version accepted for publication in MNRAS
Data_BoundaryLayerMeteorology_2021 (15 files shared)
Creators: name: Guo, Xiao-Feng
Publisher: name: figshare
Year: 2021
Subjects: subject: Atmospheric Sciences
subject: FOS: Earth and related environmental sciences

description: Please read the document "Readme_FYI.dat" (last updated: 5 August 2021) prior to your use of our data, as are published in support of Figures 3b,c, 4b, 8, 9 & 10 of the following peer-reviewed research paper: Katabatic flow structures indicative of the flux dissimilarity for stable stratification
(doi: to appear; Boundary-Layer Meteorology)
Coexistence of the Pseudogap and the Superconducting Gap Revealed by the \textit{c}-axis Optical Study of YBa$_{2}$(Cu$_{1-x}$Zn$_{x}$)$_{3}$O$_{7-δ}$
Creators: name: Uykur, Ece
name: Tanaka, Kiyohisa
name: Masui, Takahiko
name: Miyasaka, Shigeki
name: Tajima, Setsuko
Publisher: name: arXiv
Year: 2013
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: To address the issue of the pseudogap in the superconducting state of the high temperature superconducting cuprates, we studied the temperature dependent redistribution of the spectral weight in the \textit{c}-axis polarized optical spectra for underdoped YBa$_{2}$(Cu$_{1-x}$Zn$_{x}$)$_{3}$O$_{7-δ}$ single crystals with $x=0,0.007,$ 0.012, and 0.04. It was found that for Zn substituted samples, the spectral weight transfer to the high energy region, which characterizes the pseudogap state, continues even below the superconducting transition temperature (\textit{T}$_{c}$), indicating the coexistence of the pseudogap and the superconducting gap. Moreover, the observation of the pseudogap in the Zn-doped non-superconducting sample gives evidence that the pseudogap is not a precursor of superconductivity.
description: 10 pages, 4 figures, accepted to JPSJ
The Origin of Dust in Early-Type Galaxies and Implications for Accretion onto Supermassive Black Holes
Creators: name: Martini, Paul
name: Dicken, Daniel
name: Storchi-Bergmann, Thaisa
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We have conducted an archival Spitzer study of 38 early-type galaxies (ETGs) in order to determine the origin of the dust in approximately half of this population. Our sample galaxies generally have good wavelength coverage from 3.6um to 160um, as well as visible-wavelength HST images. We use the Spitzer data to estimate dust masses, or establish upper limits, and find that all of the ETGs with dust lanes in the HST data are detected in all of the Spitzer bands and have dust masses of ~10^{5-6.5} Msun, while galaxies without dust lanes are not detected at 70um and 160um and typically have <10^5 Msun of dust. The apparently dust-free galaxies do have 24um emission that scales with the shorter wavelength flux, yet substantially exceeds the expectations of photospheric emission by approximately a factor of three. We conclude this emission is dominated by hot, circumstellar dust around evolved stars that does not survive to form a substantial interstellar component. The order of magnitude variations in dust masses between galaxies with similar stellar populations rules out a subtantial contribution from continual, internal production in spite of the clear evidence for circumstellar dust. We demonstrate that the interstellar dust is not due to purely external accretion, unless the product of the merger rate of dusty satellites and the dust lifetime is at least an order of magnitude higher than expected. We propose that dust in ETGs is seeded by external accretion, yet the accreted dust is maintained by continued growth in externally-accreted cold gas beyond the nominal lifetime of individual grains. The several Gyr depletion time of the cold gas is long enough to reconcile the fraction of dusty ETGs with the merger rate of gas-rich satellites. As the majority of dusty ETGs are also low-luminosity AGN and likely fueled by this cold gas, their lifetime should similarly be several Gyr.
description: ApJ Accepted. 22 pages, 15 figures in emulateapj format
Anticipated Effects of the Bureau of Reclamation Program on Agricultural Production and Prices
Creators: name: Gertel, Karl
name: Gertel, Karl
Publisher: name: Unknown
Year: 1976
Subjects: Agricultural and Food Policy
Crop Production/Industries
Demand and Price Analysis
Land Economics/Use
Productivity Analysis
Research Methods/ Statistical Methods
Resource /Energy Economics and Policy

description: Excerpts from the report: The purpose of the overall investigation is to provide some of the facts needed to resolve a major issue in planning and evaluating Federal water resource projects. The issue concerns the appropriate level of prices to be used in determining the benefits of agricultural production increases from Federal water projects. The objective of this research is to determine whether the issue posed is a significant one: do all projects combined significantly affect U. S. production and farm prices? If the answer is yes, then a secondary objective is to indicate some of the conceptual questions that need to be answered to derive appropriate prices for evaluating the benefits of increased agricultural production from Federal water projects. A third objective is to propose some interim price adjustments for project evaluation under future conditions of a market economy unrestrained by government production controls.
Error Performance and Diversity Analysis of Multi-Source Multi-Relay Wireless Networks with Binary Network Coding and Cooperative MRC
Creators: name: Di Renzo, Marco
name: Iezzi, Michela
name: Graziosi, Fabio
Publisher: name: arXiv
Year: 2013
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: In this paper, we contribute to the theoretical understanding, the design, and the performance evaluation of multi-source multi-relay network-coded cooperative diversity protocols. These protocols are useful to counteract the spectral inefficiency of repetition-based cooperation. We provide a general analytical framework for analysis and design of wireless networks using the Demodulate-and-Forward (DemF) protocol with binary Network Coding (NC) at the relays and Cooperative Maximal Ratio Combining (C-MRC) at the destination. Our system model encompasses an arbitrary number of relays which offer two cooperation levels: i) full-cooperative relays, which postpone the transmission of their own data frames to help the transmission of the sources via DemF relaying and binary NC; and ii) partial-cooperative relays, which exploit NC to transmit their own data frames along with the packets received from the sources. The relays can apply NC on different subsets of sources, which is shown to provide the sources with unequal diversity orders. Guidelines to choose the packets to be combined, i.e., the network code, to achieve the desired diversity order are given. Our study shows that partial-cooperative relays provide no contribution to the diversity order of the sources. Theoretical findings and design guidelines are validated through extensive Monte Carlo simulations.
description: accepted, IEEE Transactions on Wireless Communications
Are there tangled magnetic fields on HgMn stars?
Creators: name: Kochukhov, O.
name: Makaganiuk, V.
name: Piskunov, N.
name: Jeffers, S. V.
name: Johns-Krull, C. M.
name: Keller, C. U.
name: Rodenhuis, M.
name: Snik, F.
name: Stempels, H. C.
name: Valenti, J. A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Several recent spectrophotometric studies failed to detect significant global magnetic fields in late-B HgMn chemically peculiar stars, but some investigations have suggested the presence of strong unstructured or tangled fields in these objects. We used detailed spectrum synthesis analysis to search for evidence of tangled magnetic fields in high-quality observed spectra of 8 slowly rotating HgMn stars and one normal late-B star. We also evaluated recent sporadic detections of weak longitudinal magnetic fields in HgMn stars based on the moment technique. Our analysis of the Zeeman broadening of magnetically sensitive spectral lines reveals no evidence of tangled magnetic fields in any of the studied HgMn or normal stars. We infer upper limits of 200-700 G for the mean magnetic field modulus -- much smaller than the field strengths implied by studies based on differential magnetic line intensification and quadratic field diagnostics. The new HARPSpol longitudinal field measurements for the extreme HgMn star HD 65949 and the normal late-B star 21 Peg are consistent with zero at a precision of 3-6 G. Re-analysis of our Stokes V spectra of the spotted HgMn star HD 11753 shows that the recent moment technique measurements retrieved from the same data are incompatible with the lack of circular polarization signatures in the spectrum of this star. We conclude that there is no evidence for substantial tangled magnetic fields on the surfaces of studied HgMn stars. We cannot independently confirm the presence of very strong quadratic or marginal longitudinal fields for these stars, so results from the moment technique are likely to be spurious.
description: 12 pages, 11 figures; accepted for publication in A&A
PSR J0357+3205: the tail of the turtle
Creators: name: Marelli, Martino
name: De Luca, Andrea
name: Salvetti, David
name: Sartore, Nicola
name: Sartori, Angelica
name: Caraveo, Patrizia
name: Pizzolato, Fabio
name: Parkinson, Pablo M. Saz
name: Belfiore, Andrea
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Using a new XMM-Newton observation, we have characterized the X-ray properties of the middle-aged radio-quiet gamma-ray pulsar J0357+3205 (named Morla) and its tail. The X-ray emission from the pulsar is consistent with a magnetospheric non-thermal origin plus a thermal emission from a hot spot (or hot spots). The lack of a thermal component from the whole surface makes Morla the coldest neutron star in its age range. We found marginal evidence for a double-peaked modulation of the X-ray emission. The study of the 9'-long tail confirmed the lack of extended emission near the pulsar itself. The tail shows a very asymmetric brightness profile and its spectrum lacks any spatial variation. We found the nebular emission to be inconsistent with a classical bow-shock, ram-pressure dominated pulsar wind nebula. We propose thermal bremsstrahlung as an alternative mechanism for Morla's tail emission. In this scenario, the tail emission comes from the shocked interstellar medium (ISM) material heated up to X-ray temperatures. This can fully explain the peculiar features of the tail, assuming a hot, moderately dense interstellar medium around the pulsar. For a bremsstrahlung-emitting tail, we can estimate the pulsar distance to be between 300 and 900 pc. A pulsar velocity of about 1900 km/s is required - which would make Morla the pulsar with the largest velocity - and high inclination angles (>70 degrees) are preferred. We propose Morla's nebula as the first example of a new "turtle's tail" class of thermally-emitting nebulae associated to high velocity pulsars.
description: 39 pages, 2 tables and 6 figures. Accepted by the Astrophysical Journal
Pair Production of a 125 GeV Higgs Boson in MSSM and NMSSM at the LHC
Creators: name: Cao, Junjie
name: Heng, Zhaoxia
name: Shang, Liangliang
name: Wan, Peihua
name: Yang, Jin Min
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In light of the recent LHC Higgs search data, we investigate the pair production of a SM-like Higgs boson around 125 GeV in the MSSM and NMSSM. We first scan the parameter space of each model by considering various experimental constraints, and then calculate the Higgs pair production rate in the allowed parameter space. We find that in most cases the dominant contribution to the Higgs pair production comes from the gluon fusion process and the production rate can be greatly enhanced, maximally 10 times larger than the SM prediction (even for a TeV-scale stop the production rate can still be enhanced by a factor of 1.3). We also calculate the chi-square value with the current Higgs data and find that in the most favored parameter region the production rate is enhanced by a factor of 1.45 in the MSSM, while in the NMSSM the production rate can be enhanced or suppressed (σ_{SUSY}/σ_{SM} varies from 0.7 to 2.4).
description: 15 pages, 5 figures
The Column Density Distribution and Continuum Opacity of the Intergalactic and Circumgalactic Medium at Redshift =2.4
Creators: name: Rudie, Gwen C.
name: Steidel, Charles C.
name: Shapley, Alice E.
name: Pettini, Max
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present new high-precision measurements of the opacity of the intergalactic and circumgalactic medium (IGM, CGM) at =2.4. Using Voigt profile fits to the full Lyman alpha and Lyman beta forests in 15 high-resolution high-S/N spectra of hyperluminous QSOs, we make the first statistically robust measurement of the frequency of absorbers with HI column densities 14 < log(NHI) < 17.2. We also present the first measurements of the frequency distribution of HI absorbers in the volume surrounding high-z galaxies (the CGM, 300 pkpc), finding that the incidence of absorbers in the CGM is much higher than in the IGM. In agreement with Rudie et al. (2012), we find that there are fractionally more high-NHI absorbers than low-NHI absorbers in the CGM compared to the IGM, leading to a shallower power law fit to the CGM frequency distribution. We use these new measurements to calculate the total opacity of the IGM and CGM to hydrogen-ionizing photons, finding significantly higher opacity than most previous studies, especially from absorbers with log(NHI) < 17.2. Reproducing the opacity measured in our data as well as the incidence of absorbers with log(NHI) > 17.2 requires a broken power law parameterization of the frequency distribution with a break near log(NHI) ~ 15. We compute new estimates of the mean free path (mfp) to hydrogen-ionizing photons at z=2.4, finding mfp = 147 +- 15 Mpc when considering only IGM opacity. If instead, we consider photons emanating from a high-z star-forming galaxy and account for the local excess opacity due to the surrounding CGM of the galaxy itself, the mean free path is reduced to mfp = 121 +- 15 Mpc. These mfp measurements are smaller than recent estimates and should inform future studies of the metagalactic UV background and of ionizing sources at z~2-3.
description: Accepted to ApJ
Searches for Large-Scale Anisotropies of Cosmic Rays: Harmonic Analysis and Shuffling Technique
Creators: name: Deligny, Olivier
name: Salamida, Francesco
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The measurement of large scale anisotropies in cosmic ray arrival directions is generally performed through harmonic analyses of the right ascension distribution as a function of energy. These measurements are challenging due to the small expected anisotropies and meanwhile the relatively large modulations of observed counting rates due to experimental effects. In this paper, we present a procedure based on the shuffling technique to carry out these measurements, applicable to any cosmic ray detector without any additional corrections for the observed counting rates.
description: 22 pages, 10 figures, to appear in Astroparticle Physics
SECURING SYSTEM AND EMBEDDED SOFTWARE VIA FUZZING
Creators: name: Kim, Kyungtae
Publisher: name: Purdue University Graduate School
Year: 2022
Subjects: Software and application security

description: System software is a lucrative target for cyber attacks due to its high privilege and large attack surfaces. While fuzzing has been proven effective for decades, recent fuzzers still suffer from limited coverage when dealing with real-world system programs, such as OS kernels, firmware due to their unique interfaces, and large input space, etc. In this thesis, we aim to secure various system and embedded software, such as OS kernels, device drivers and firmware, using proposed fuzzing techniques tailored for each system software. First, we present HFL, hybrid fuzzing for the Linux kernel. HFL achieves hybrid kernel fuzzing scheme with a faithful combination of traditional fuzzing and concolic execution. Furthermore, HFL addresses essential challenges in the Linux kernel via three distinct features: 1) converting indirect control transfers to direct transfers, 2) inferring system call dependencies, and 3) identifying nested arguments structures. HFL found 24 previously unknown bugs in different Linux kernels, and achieved higher code coverage than baseline kernel fuzzers. While the security of USB host stacks has gotten lots of attention, USB gadget stacks are left behind, leaving their vulnerabilities unfixed. To secure USB gadget stacks, we propose the first USB gadget stack fuzzing, FuzzUSB. As a stateful fuzzer, FuzzUSB extracts USB gadget state machines from USB gadget drivers, and uses them to achieve state-guided fuzzing through multi-channel inputs. FuzzUSB has found total 34 previously-unknown bugs within the Linux and Android kernels, and demonstrated improved bug-finding efficiency with high code coverage. As USB Power Delievery (USBPD) is becoming prevalent, but vulnerable to cyber attacks, there is an increasing need for its security. To achieve secure USBPD communications, we propose FuzzPD, the first black-box USBPD fuzzing technique. FuzzPD leverages a dual-role state machine extracted from USBPD specifications. Guided by the dual-role state machine, FuzzPD performs multi-level mutations, not only achieving state-coverage guided mutation for inter-state exploration, but also leveraging input seeding especially for in-state mutation. FuzzPD discovered 45 USBPD bugs in total, ranging from over-charging bugs to memory access violation.
Non-Degenerate Squarks from Flavored Gauge Mediation
Creators: name: Galon, Iftah
name: Perez, Gilad
name: Shadmi, Yael
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study the squark spectra of Flavored Gauge Mediation Models, in which messenger-matter superpotential couplings generate new, generation-dependent contributions to the squark masses. The new couplings are controlled by the same flavor symmetry that explains the fermion masses, leading to excellent alignment of the quark and squark mass matrices. This allows for large squark mass splittings consistent with all flavor bounds. In particular, second-generation squarks are often significantly lighter than the first-generation squarks. As squark production at the LHC is dominated by the up- and down-squarks and the efficiencies for squark searches increase with their masses, the charm and/or strange squark masses can be well below the current LHC bounds. At the same time, even with a single set of messengers, the models can generate large stop mixings which result in large loop contributions to the Higgs mass.
description: 16 pages, 2 figures. v2: Typo corrected, references added
Confronting the models of 3:2 QPOs with the evidence of near extreme Kerr black hole
Creators: name: Kotrlova, Andrea
name: Torok, Gabriel
name: Sramkova, Eva
name: Stuchlik, Zdenek
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The black hole mass and spin estimates assuming various specific models of the 3:2 high frequency quasi-periodic oscillations (HF QPOs) have been carried out in Torok et al. (2005, 2011). Here we briefly summarize some current points. Spectral fitting of the spin a=cJ/GM^2 in the microquasar GRS 1915+105 reveals that this system can contain a near extreme rotating black hole (e.g., McClintock et al. 2011). Confirming the high value of the spin would have significant consequences for the theory of the HF QPOs. The estimate of a>0.9 is almost inconsistent with the relativistic precession (RP), tidal disruption (TD), and the warped disc (WD) model. The epicyclic resonance (Ep) and discoseismic models assuming the c- and g- modes are instead favoured. However, consideration of all three microquasars that display the 3:2 HF QPOs leads to a serious puzzle because the differences in the individual spins, such as a=0.9 compared to a=0.7, represent a generic problem almost for any unified orbital 3:2 QPO model.
description: 2 pages, to be published in Proceedings of IAUS 290 "Feeding Compact Objects: Accretion on All Scales", C. M. Zhang, T. Belloni, M. Mendez and S. N. Zhang (eds.)
Magnetic penetration depth in single crystals of SrPd$_2$Ge$_2$ superconductor
Creators: name: Kim, H.
name: Sung, N. H.
name: Cho, B. K.
name: Tanatar, M. A.
name: Prozorov, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The in-plane magnetic penetration depth, $λ_m(T)$, was measured in single crystals of SrPd$_2$Ge$_2$ superconductor in a dilution refrigerator down to T=60 mK and in magnetic fields up to $H_{dc} = 1$ T by using a tunnel diode resonator. The London penetration depth, $λ$, saturates exponentially approaching $T\rightarrow 0$ indicating fully gapped superconductivity. The thermodynamic Rutgers formula was used to estimate $λ(0) = 426$ nm which was used to calculate the superfluid density, $ρ_s(T)=λ^2(0)/λ^2(T)$. Analysis of $ρ_s(T)$ in the full temperature range shows that it is best described by a single - gap behavior, perhaps with somewhat stronger coupling. In a magnetic field, the measured penetration depth is given by the Campbell penetration depth which was used to calculate the theoretical critical current density $j_c$. For $H \le 0.45$ T, the strongest pinning is achieved not at the lowest, but at some intermediate temperature, probably due to matching effect between temperature - dependent coherence length and relevant pinning lengthscale. Finally, we find a compelling evidence for surface superconductivity. Combining all measurements, the entire $H$-$T$ phase diagram of SrPd$_2$Ge$_2$ is constructed with an estimated $H_{c2}(0)=0.4817$ T.
Evidence for Helical Nuclear Spin Order in GaAs Quantum Wires
Creators: name: Scheller, C. P.
name: Liu, T. -M.
name: Barak, G.
name: Yacoby, A.
name: Pfeiffer, L. N.
name: West, K. W.
name: Zumbühl, D. M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present transport measurements of cleaved edge overgrowth GaAs quantum wires. The conductance of the first mode reaches 2 e^2/h at high temperatures T > 10 K, as expected. As T is lowered, the conductance is gradually reduced to 1 e^2/h, becoming T-independent at T < 0.1 K, while the device cools far below 0.1 K. This behavior is seen in several wires, is independent of density, and not altered by moderate magnetic fields B. The conductance reduction by a factor of two suggests lifting of the electron spin degeneracy in absence of B. Our results are consistent with theoretical predictions for helical nuclear magnetism in the Luttinger liquid regime.
description: 5 pages, 4 figures (color)
Multi-resonance orbital model of HF QPOs
Creators: name: Stuchlik, Zdenek
name: Kotrlova, Andrea
name: Torok, Gabriel
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Using known frequencies of the twin peak high-frequency quasiperiodic oscillations (HF QPOs) and known mass M of the central black hole, the black-hole dimensionless spin a can be determined assuming a concrete version of the resonance model. However, large range of observationally limited values of the black hole mass implies a low precision of the spin estimates. We discuss the possibility of higher precision of the black hole spin measurements in the framework of multi-resonance model inspired by observations of more than two HF QPOs in some black hole sources. We determine the spin and mass dependence of the twin peak frequencies with a general rational ratio n:m assuming a non-linear resonance of oscillations with the epicyclic and Keplerian frequencies or their combinations. In the multi-resonant model, the twin peak resonances are combined properly to give the observed frequency set. We focus on the special case of duplex frequencies, when the top, bottom, or mixed frequency is common at two different radii where the resonances occur giving triple frequency sets.
description: 2 pages, to be published in Proceedings of IAUS 290 "Feeding Compact Objects: Accretion on All Scales", C. M. Zhang, T. Belloni, M. Mendez and S. N. Zhang (eds.)
Random matrix model for free Meixner laws
Creators: name: Lenczewski, Romuald
Publisher: name: arXiv
Year: 2013
Subjects: subject: Operator Algebras (math.OA)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 46L53, 46L54, 15B52

description: Applying the concept of matricial freeness which generalizes freeness in free probability, we have recently studied asymptotic joint distributions of symmetric blocks of Gaussian random matrices (Gaussian Symmetric Block Ensemble). This approach gives a block refinement of the fundamental result of Voiculescu on asymptotic freeness of independent Gaussian random matrices. In this paper, we show that this framework is natural for constructing a random matrix model for free Meixner laws. We also demonstrate that the ensemble of independent matrices of this type is asymptotically conditionally free with respect to the pair of partial traces.
description: 18 pages, minor revisions
A search for flavor-changing non-standard neutrino interactions by MINOS
Creators: name: MINOS Collaboration
name: Adamson, P.
name: Barr, G.
name: Bishai, M.
name: Blake, A.
name: Bock, G. J.
name: Bogert, D.
name: Cao, S. V.
name: Cherdack, D.
name: Childress, S.
name: Coelho, J. A. B.
name: Corwin, L.
name: Cronin-Hennessy, D.
name: de Jong, J. K.
name: Devan, A. V.
name: Devenish, N. E.
name: Diwan, M. V.
name: Escobar, C. O.
name: Evans, J. J.
name: Falk, E.
name: Feldman, G. J.
name: Frohne, M. V.
name: Gallagher, H. R.
name: Gomes, R. A.
name: Goodman, M. C.
name: Gouffon, P.
name: Graf, N.
name: Gran, R.
name: Grzelak, K.
name: Habig, A.
name: Hartnell, J.
name: Hatcher, R.
name: Himmel, A.
name: Holin, A.
name: Hylen, J.
name: Irwin, G. M.
name: Isvan, Z.
name: James, C.
name: Jensen, D.
name: Kafka, T.
name: Kasahara, S. M. S.
name: Koizumi, G.
name: Kordosky, M.
name: Kreymer, A.
name: Lang, K.
name: Ling, J.
name: Litchfield, P. J.
name: Lucas, P.
name: Mann, W. A.
name: Marshak, M. L.
name: Mathis, M.
name: Mayer, N.
name: Medeiros, M. M.
name: Mehdiyev, R.
name: Meier, J. R.
name: Messier, M. D.
name: Miller, W. H.
name: Mishra, S. R.
name: Sher, S. Moed
name: Moore, C. D.
name: Mualem, L.
name: Mufson, S.
name: Musser, J.
name: Naples, D.
name: Nelson, J. K.
name: Newman, H. B.
name: Nichol, R. J.
name: Nowak, J. A.
name: Oliver, W. P.
name: Orchanian, M.
name: Pahlka, R. B.
name: Paley, J.
name: Patterson, R. B.
name: Pawloski, G.
name: Phan-Budd, S.
name: Plunkett, R. K.
name: Qiu, X.
name: Radovic, A.
name: Rebel, B.
name: Rosenfeld, C.
name: Rubin, H. A.
name: Sanchez, M. C.
name: Schneps, J.
name: Schreckenberger, A.
name: Schreiner, P.
name: Sharma, R.
name: Sousa, A.
name: Tagg, N.
name: Talaga, R. L.
name: Thomas, J.
name: Thomson, M. A.
name: Toner, R.
name: Torretta, D.
name: Tzanakos, G.
name: Urheim, J.
name: Vahle, P.
name: Viren, B.
name: Weber, A.
name: Webb, R. C.
name: White, C.
name: Whitehead, L.
name: Wojcicki, S. G.
name: Zwaska, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We report new constraints on flavor-changing non-standard neutrino interactions (NSI) using data from the MINOS experiment. We analyzed a combined set of beam neutrino and antineutrino data, and found no evidence for deviations from standard neutrino mixing. The observed energy spectra constrain the NSI parameter to the range $-0.20 < \varepsilon_{μτ} < 0.07\;\text{(90% C.L.)}$
Universality for Moving Stripes: A Hydrodynamic Theory of Polar Active Smectics
Creators: name: Chen, Leiming
name: Toner, John
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We present a hydrodynamic theory of polar active smectics, for systems both with and without number conservation. For the latter, we find quasi long-ranged smectic order in d=2 and long-ranged smectic order in d=3. In d=2 there is a Kosterlitz-Thouless type phase transition from the smectic phase to the ordered fluid phase driven by increasing the noise strength. For the number conserving case, we find that giant number fluctuations are greatly suppressed by the smectic order; that smectic order is long-ranged in d=3; and that nonlinear effects become important in d=2.
description: 6 pages, 2 figures
The SLUGGS survey: Probing the supermassive black hole connection with bulges and haloes using red and blue globular cluster systems
Creators: name: Pota, Vincenzo
name: Graham, Alister W.
name: Forbes, Duncan A.
name: Romanowsky, Aaron J.
name: Brodie, Jean P.
name: Strader, Jay
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Understanding whether the bulge or the halo provides the primary link to the growth of supermassive black holes has strong implications for galaxy evolution and supermassive black hole formation itself. In this paper, we approach this issue by investigating extragalactic globular cluster (GC) systems, which can be used to probe the physics of both the bulge and the halo of the host galaxy. We study the relation between the supermassive black hole masses M_BH and the globular cluster system velocity dispersions sigma_GC using an updated and improved sample of 21 galaxies. We exploit the dichotomy of globular cluster system colours, to test if the blue and red globular clusters correlate differently with black hole mass. This may be expected if they trace the potentially different formation history of the halo and of the bulge of the host galaxy respectively. We find that M_BH correlates with the total GC system velocity dispersion, although not as strongly as claimed by recent work of Sadoun & Colin. We also examine the M_BH - sigma_GC relation for barred/bar-less and core/non-core galaxies, finding no significant difference, and for the first time we quantify the impact of radial gradients in the GC system velocity dispersion profile on the M_BH - sigma_GC relation. We additionally predict M_BH in 13 galaxies, including dwarf elliptical galaxies and the cD galaxy NGC 3311. We conclude that our current results cannot discriminate between the bulge/halo scenario. Although there is a hint that the red GC velocity dispersion might correlate better with M_BH than the blue GC velocity dispersion, the number statistics are still too low to be certain.
description: 9 pages, 5 figures, accepted for publication in MNRAS, For more information about the SLUGGS Survey see http://sluggs.swin.edu.au/