Miracle-dz/UniFAR-FTUs huggingface dataset:
CLUSTERING PROPERTIES AND HALO MASSES FOR CENTRAL GALAXIES IN THE LOCAL UNIVERSE

We investigate the clustering and dark matter halo mass for a sample of ∼16,000 central galaxies selected from the SDSS/DR7 group catalog. We select subsamples of central galaxies on three two-dimensional planes, each formed by stellar mass (M * ? > ) and one other property out of optical color (g − r), surface stellar mass density ( &mgr; * ? > ), and central stellar velocity dispersion ( &sgr; * ? > ). For each subsample we measure both the projected cross-correlation function ( w p ( r p ) ? > ) relative to a reference galaxy sample, and an average mass of the host dark matter halos (M h ? > ). Both w p ( r p ) ? > and M h ? > show the strongest dependence on M * ? > , and there is no clear dependence on the other properties when M * ? > is fixed. This result provides strong support to the previously adopted assumption that, for central galaxies, stellar mass is the best indicator of the host dark halo mass. For comparison we have estimated w p ( r p ) ? > for the full galaxy population and the population of satellite galaxies. Both populations show similar clustering properties in all cases, but they are similar to the centrals only at high masses (M * ? > ≳ 10 11 ? > M ⊙ ? > ). At lower masses, their w p ( r p ) ? > depends more strongly on &sgr; * ? > and g − r than on M * ? > . It is thus necessary to consider central and satellite galaxies separately when studying the link between galaxies and dark matter halos. We discuss the implications of our results for the relative roles of halo mass and galaxy structure in quenching the star formation in central galaxies.
Distinctive response of many-body localized systems to a strong electric field

We study systems that are close to or within the many-body localized (MBL) regime and are driven by a strong electric field. In the ergodic regime, the disorder extends the applicability of the equilibrium linear-response theory to stronger drivings, whereas the response of the MBL systems is very distinctive, revealing currents with damped oscillations. The oscillation frequency is independent of driving and the damping is not due to heating but rather due to dephasing. The details of damping depend on the system's history reflecting the nonergodicity of the MBL phase, while the frequency of the oscillations remains a robust hallmark of localization. Our results suggest that another distinctive characteristic of the driven MBL phase is also a logarithmic increase of the energy and the polarization with time.
Supporting the psychological health of our first-year students: An arts-based community magic workshop for adapting to university

: The arts have long been intertwined with wellbeing and empirical attention is shifting back toward the wellbeing value of the arts. One art that has been applied in educational contexts but received limited empirical attention is that of achieving the impossible, namely, the art of performing magic. While research is young, reviews on the wellbeing-value of magic have revealed theoretical frameworks suggesting its potential to enhance self-processes and social aspects. These aspects are especially important for university students to have a psychologically healthy transition to university life because it involves integrating one’s adult identity with the self, which can challenge one’s self-esteem. Thus, the present study investigated how community magic workshops affect self-esteem, wellbeing, closeness, and sense of belonging for first-year university students in London. Students were allocated to either magic workshops where they learned magic tricks or mindfulness workshops during their first university term. Measures were taken at baseline, post-intervention, and a one-month follow-up. Both groups improved on all measures but students in magic workshops perceived greater benefits than the mindfulness group. Results provide preliminary evidence for using magic-based workshops as an appealing, preventative intervention that enhances the college experience for first-year students.
O C ] 1 N ov 2 02 2 LINEAR OPTIMIZATION OVER HOMOGENEOUS MATRIX CONES

A convex cone is homogeneous if its automorphism group acts transitively on the interior of the cone. Cones that are homogeneous and self-dual are called symmetric. Conic optimization problems over symmetric cones have been extensively studied in convex optimization, in particular in the literature on interior-point algorithms, and as the foundation of modeling tools for convex optimization. In this paper, we consider the less well-studied conic optimization problems over cones that are homogeneous but not necessarily self-dual. We start with cones of positive semidefinite symmetric matrices with a given sparsity pattern. Homogeneous cones in this class are characterized by nested block-arrow sparsity patterns, a subset of the chordal sparsity patterns. Chordal sparsity guarantees that positive define matrices in the cone have zero-fill Cholesky factorizations. The stronger properties that make the cone homogeneous guarantee that the inverse Cholesky factors have the same zero-fill pattern. We describe transitive subsets of the cone automorphism groups, and important properties of the composition of log-det barriers with the automorphisms. Next, we consider extensions to linear slices of the positive semidefinite cone, and review conditions that make such cones homogeneous. An important example is the matrix norm cone, the epigraph of a quadratic-over-linear matrix function. The properties of homogeneous sparse matrix cones are shown to extend to this more general class of homogeneous matrix cones. In the third part we give an overview of the algebraic theory of homogeneous cones due to Vinberg and Rothaus. A fundamental consequence of this theory is that every homogeneous cone admits a spectrahedral (linear matrix inequality) representation. We conclude by discussing the role of homogeneous structure in primal–dual symmetric interiorpoint methods. We make a contrast with the well-developed algorithms for symmetric cones that exploit the strong properties of self-scaled barriers, and with symmetric primal–dual methods for general convex cones.
Closed-form expression for the Goos-Hänchen lateral displacement

The Artmann formula provides an accurate determination of the Goos-Hanchen lateral displacement in terms of the light wavelength, refractive index and in- cidence angle. In the total reflection region, this formula is widely used in the literature and confirmed by exper- iments. Nevertheless, for incidence at critical angle, it tends to infinity and numerical calculations are needed to reproduce the experimental data. In this paper, we overcome the divergence problem at critical angle and find, for Gaussian beams, a closed formula in terms of modified Bessel functions of the first kind. The for- mula is in excellent agreement with numerical calcula- tions and reproduces, for incidence angles greater than critical ones, the Artmann formula. The closed form also allows one to understand how the breaking of sym- metry in the angular distribution is responsible for the difference between measurements done by considering the maximum and the mean value of the beam inten- sity. The results obtained in this study clearly show the Goos-Hanchen lateral displacement dependence on the angular distribution shape of the incoming beam. Finally, we also present a brief comparison with experi- mental data and other analytical formulas found in the literature.
Influence of dephasing on many-body localization

We study the effects of dephasing noise on a prototypical many-body localized system -- the XXZ spin 1/2 chain with a disordered magnetic field. At times longer than the inverse dephasing strength the dynamics of the system is described by a probabilistic Markov process on the space of diagonal density matrices, while all off-diagonal elements of the density matrix decay to zero. The generator of the Markovian process is a bond-disordered spin chain. The scaling variable is identified, and independence of relaxation on the interaction strength is demonstrated. We show that purity and von Neumann entropy are extensive, showing no signatures of localization, while the operator space entanglement entropy exhibits a logarithmic growth with time until the final saturation corresponding to localization breakdown, suggesting a many-body localized dynamics of the effective Markov process.
THE INTRACLUSTER PLASMA: A UNIVERSAL PRESSURE PROFILE?

The pressure profiles of the intracluster plasma in galaxy clusters show a wide variance when observed in X-rays at low redshifts, z ≲ 0.2. We find the profiles to follow two main patterns, featuring either a steep or a shallow shape throughout both core and outskirts. We trace these shapes back to a physical dichotomy of clusters into two classes, marked by either low entropy (LE) or high entropy (HE) throughout. From X-ray observations and Sunyaev–Zel'dovich (SZ) stacked data at higher redshifts 0.2 ≲ z ≲ 0.4, we obtain evidence of an increasing abundance of HEs relative to LEs. We propose this to constitute a systematic trend toward high z; specifically, we predict the pressure profiles to converge into a truly universal HE-like template for z ≳ 0.5. We submit our physical templates and converging trend for further observational tests, in view of current and upcoming measurements of individual, stacked, and integrated SZ signals.
Determining the stellar masses of submillimetre galaxies: the critical importance of star formation histories

Submillimetre (submm) galaxies are among the most rapidly star-forming and most massive high-redshift galaxies; thus, their properties provide important constraints on galaxy evolution models. However, there is still a debate about their stellar masses and their nature in the context of the general galaxy population. To test the reliability of their stellar mass determinations, we used a sample of simulated submm galaxies for which we derived stellar masses via spectral energy distribution (SED) modelling (with Grasil, Magphys, Hyperz and LePhare) adopting various star formation histories (SFHs). We found that the assumption of SFHs with two independent components leads to the most accurate stellar masses. Exponentially declining SFHs (tau) lead to lower masses (albeit still consistent with the true values), while the assumption of single-burst SFHs results in a significant mass underestimation. Thus, we conclude that studies based on the higher masses inferred from fitting the SEDs of real submm galaxies with double SFHs are most likely to be correct, implying that submm galaxies lie on the high-mass end of the main sequence of star-forming galaxies. This conclusion appears robust to assumptions of whether or not submm galaxies are driven by major mergers, since the suite of simulated galaxies modelled here contains examples of both merging and isolated galaxies. We identified discrepancies between the true and inferred stellar ages (rather than the dust attenuation) as the primary determinant of the success/failure of the mass recovery. Regardless of the choice of SFH, the SED-derived stellar masses exhibit a factor of ~2 scatter around the true value; this scatter is an inherent limitation of the SED modelling due to simplified assumptions. Finally, we found that the contribution of active galactic nuclei does not have any significant impact on the derived stellar masses.
THE YOUNG CLUSTER IN IC 1274

IC 1274 is a faintly luminous nebula lying on the near surface of the Lynds 227 (L227) molecular cloud. Its cavity-like morphology is reminiscent of a blistered star-forming region. Four luminous, early-type (B0–B5) stars are located within a spherical volume ∼5′ in diameter that appears to be clear of heavy obscuration. Approximately centered in the cleared region is the B0 V star HD 166033, which is thought to be largely responsible for the cavity's excavation. Over 80 Hα emission sources brighter than V ∼ 21 have been identified in the region. More than half of these are concentrated in IC 1274 and are presumably members of a faint T Tauri star population. Chandra Advanced CCD Imaging Spectrometer imaging of a nearby suspected pulsar and time-variable γ-ray source (GeV J1809−2327) detected 21 X-ray sources in the cluster vicinity, some of which are coincident with the early-type stars and Hα emitters in IC 1274. Deep (V ∼ 22) optical BVRI photometry has been obtained for the cluster region. A distance of 1.82 ± 0.3 kpc and a mean extinction of AV ∼ 1.21 ± 0.2 mag follow from photometry of the early-type stars. Using pre-main-sequence evolutionary models, we derive a median age for the Hα emitters and X-ray sources of ∼1 Myr; however, a significant dispersion is present. Our interpretation of the structure of IC 1274 and the spatial distribution of Hα emitters is that the early-type stars formed recently and are in the process of ionizing and dispersing the molecular gas on the near surface of L227. The displaced material was driven against what remains of the molecular cloud to the east, enabling the formation of the substantial number of T Tauri stars found there. A dispersed population of Hα emitters is also found along the periphery of L227, IC 1275, and IC 4684. These sources, if pre-main-sequence stars, appear to have formed in relative isolation compared to the dense cluster environment of IC 1274 or, alternatively, may be older and have drifted further from their formation sites. We identify a V ∼ 21.5 star very near the position of X-ray source 5, the assumed γ-ray source and young pulsar candidate. However, the lack of distinctive characteristics for this source, coupled with the density of faint stars in this region, suggest that this may be a random superposition.
Bulk motion measurements in clusters of galaxies with ATHENA-like missions

The hierarchical formation of clusters of galaxies by accretion of material releases gravitational energy which dissipates into the intracluster gas. The process heats the material and generates gas turbulence and bulk motions and thus kinetic pressure. Mapping the velocity fields of the moving subunits would enable a new diagnostics tool for cluster formation studies and unbiased X-ray mass estimates. The required spatially resolved high resolution spectroscopy is not currently available. I demonstrate here the feasibility of detecting and mapping the velocities of the bulk motions using the Doppler shift of the Fe XXV K alpha line with the proposed ATHENA satellite.
FUV IRRADIATED DISK ATMOSPHERES: LYα AND THE ORIGIN OF HOT H2 EMISSION

Protoplanetary disks are strongly irradiated by a stellar FUV spectrum that is dominated by Ly &agr; ? > photons. We investigate the impact of stellar Ly &agr; ? > irradiation on the terrestrial planet region of disks (≲1 AU) using an updated thermal-chemical model of a disk atmosphere irradiated by stellar FUV and X-rays. The radiative transfer of Ly &agr; ? > is implemented in a simple approach that includes scattering by H i and absorption by molecules and dust. Because of their non-radial propagation path, scattered Ly &agr; ? > photons deposit their energy deeper in the disk atmosphere than the radially propagating FUV continuum photons. We find that Ly &agr; ? > has a significant impact on the thermal structure of the atmosphere. Photochemical heating produced by scattered Ly &agr; ? > photons interacting with water vapor and OH leads to a layer of hot (1500–2500 K) molecular gas. The temperature in the layer is high enough to thermally excite the H 2 ? > to vibrational levels from which they can be fluoresced by Ly &agr; ? > to produce UV fluorescent H 2 ? > emission. The resulting atmospheric structure may help explain the origin of UV fluorescent H 2 ? > that is commonly observed from classical T Tauri stars.
Why momentum width matters for atom interferometry with Bragg pulses

We theoretically consider the effect of the atomic source's momentum width on the efficiency of Bragg mirrors and beamsplitters and, more generally, on the phase sensitivity of Bragg pulse atom interferometers. By numerical optimization, we show that an atomic cloud's momentum width places a fundamental upper bound on the maximum transfer efficiency of a Bragg mirror pulse, and furthermore limits the phase sensitivity of a Bragg pulse atom interferometer. We quantify these momentum width effects, and precisely compute how mirror efficiencies and interferometer phase sensitivities vary as functions of Bragg order and source type. Our results and methodology allow for an efficient optimization of Bragg pulses and the comparison of different atomic sources, and will help in the design of large momentum transfer Bragg mirrors and beamsplitters for use in atom-based inertial sensors.
Hyperons and massive neutron stars: Vector repulsion and SU(3) symmetry

With the discovery of massive neutron stars such as PSR J1614-2230, the question has arisen of whether exotic matter such as hyperons can exist in the neutron star core. We examine the conditions under which hyperons can exist in massive neutron stars. We consistently investigate the vector baryon-meson coupling, going from the SU(6) quark model to a broader SU(3) symmetry. We propose that the maximum neutron star mass decreases linearly with the strangeness content ${f}_{s}$ of the neutron star core as ${M}_{\text{max}}({f}_{s})={M}_{\text{max}}(0)\ensuremath{-}0.6{M}_{\ensuremath{\bigodot}}({f}_{s}/0.1)$, which seems to be independent of the underlying nuclear equation of state and the vector baryon-meson coupling scheme. Thus, pulsar mass measurements can be used to constrain the hyperon fraction in neutron stars.
Efficient continuous-wave nonlinear frequency conversion in high-Q gallium nitride photonic crystal cavities on silicon

We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitation. Optimized two-dimensional PhC cavities with augmented far-field coupling have been characterized with quality factors as high as 4.4 × 104, approaching the computed theoretical values. The strong enhancement in light confinement has enabled efficient SHG, achieving a normalized conversion efficiency of 2.4 × 10−3 W−1, as well as simultaneous THG. SHG emission power of up to 0.74 nW has been detected without saturation. The results herein validate the suitability of gallium nitride for integrated nonlinear optical processing.
Erratum: Discovery of the infrared counterpart of CXOU J174437.3–323222 in the field of IGR J17448–3232: a blazar candidate viewed through the Galactic Centre?

We present our near-infrared ESO-NTT KS band observations of the field of IGR J17448−3232 which show no extended emission consistent with the supernova remnant (SNR), but in which we identify a new counterpart, also visible in Spitzer images up to 24 μm, at the position of the X-ray point source, CXOU J174437.3−323222. Multiwavelength spectral modelling shows that the data are consistent with a reddened and absorbed single power law over 5 orders of magnitude in frequency. This implies non-thermal, possibly synchrotron emission that renders the previous identification of this source as a possible pulsar, and its association to the SNR, unlikely; we instead propose that the emission may be due to a blazar viewed through the plane of the Galaxy.
Kinetic description of quasi-stationary axisymmetric collisionless accretion disk plasmas with arbitrary magnetic field configurations

A kinetic treatment is developed for collisionless magnetized plasmas occurring in high-temperature, low-density astrophysical accretion disks, such as are thought to be present in some radiatively inefficient accretion flows onto black holes. Quasi-stationary configurations are investigated, within the framework of a Vlasov-Maxwell description. The plasma is taken to be axisymmetric and subject to the action of slowly time-varying gravitational and electromagnetic fields. The magnetic field is assumed to be characterized by a family of locally nested but open magnetic surfaces. The slow collisionless dynamics of these plasmas is investigated, yielding a reduced gyrokinetic Vlasov equation for the kinetic distribution function. For doing this, an asymptotic quasi-stationary solution is first determined, represented by a generalized bi-Maxwellian distribution expressed in terms of the relevant adiabatic invariants. The existence of the solution is shown to depend on having suitable kinetic constraints and .
Experimental observation of shear thickening oscillation

We report experimental observations of the shear thickening oscillation, i.e. the spontaneous macroscopic oscillation in the shear flow of severe shear thickening fluid. Using a density-matched starch-water mixture, in the cylindrical shear flow of a few centimeters flow width, we observed that well-marked vibrations of frequency around 20 Hz appear via a Hopf bifurcation upon increasing externally applied shear stress. The parameter range and the frequency of the vibration are consistent with those expected by a simple phenomenological model of the dilatant fluid.
HST/COS detection of a Ne viii absorber towards PG 1407+265: an unambiguous tracer of collisionally ionized hot gas?

We report the detection of Ne VIII in a z_abs = 0.59961 absorber towards the QSO PG 1407+265 (z_em = 0.94). Besides Ne VIII, absorption from HI Lyman series lines (HI 1025 - 915), several other low (C II, N II, O II, and S II), intermediate (C III, N III, N IV, O III, S IV, and S V) and high (S VI, O VI, and Ne VIII) ionization metal lines are detected. Disparity in the absorption line kinematics between different ions implies that the absorbing gas comprises of multiple ionization phases. The low and the intermediate ions (except S V) trace a compact (~ 410 pc), metal-rich (Z ~ Z_sun) and over-dense (log n_H ~ -2.6) photoionized region that sustained star-formation for a prolonged period. The high ions, Ne VIII and O VI, can be explained as arising in a low density (-5.3 Z_sun) and diffuse (~ 180 kpc) photoionized gas. The S V, S VI and C IV (detected in the FOS spectrum) require an intermediate photoionization phase with -4.2 < log n_H < -3.5. Alternatively, a pure collisional ionization model, as used to explain the previous known Ne VIII absorbers, with 5.65 < log T < 5.72, can reproduce the S VI, O VI, and Ne VIII column densities simultaneously in a single phase. However, even such models require an intermediate phase to reproduce any observable S V and/or C IV. Therefore, we conclude that when multiple phases are present, the presence of Ne VIII is not necessarily an unambiguous indication of collisionally ionized hot gas.
Nonlinear self-adjointness in constructing conservation laws

The general concept of nonlinear self-adjointness of differential equations is introduced. It includes the linear self-adjointness as a particular case. Moreover, it embraces the previous notions of self-adjoint and quasi self-adjoint nonlinear equations. The class of nonlinearly self-adjoint equations includes, in particular, all linear equations. Conservation laws associated with symmetries can be constructed for all nonlinearly self-adjoint differential equations and systems. The number of equations in systems can be different from the number of dependent variables.