Miracle-dz/UniFAR-FTUs huggingface dataset:
Accepted for Publication in the Astrophysical Journal the Regulation of Cooling and Star Formation in Luminous Galaxies by Agn Feedback and the Cooling-time/entropy Threshold for the Onset of Star Formation

Using broadband optical imaging and Chandra X-ray data for a sample of 46 cluster central dominant galaxies (CDGs), we investigate the connection between star formation, the intracluster medium (ICM), and the central active galactic nucleus (AGN). We report the discovery of a remarkably sharp threshold for the onset of star formation that occurs when the central cooling time of the hot atmosphere falls below ∼ 5 × 10 8 yr, or equivalently when the central entropy falls below ∼ 30 keV cm 2. In addition to this criterion, star formation in cooling flows also appears to require that the X-ray and galaxy centroids lie within ∼ 20 kpc of each other, and that the jet (cavity) power is smaller than the X-ray cooling luminosity. These three criteria, together with the high ratio of cooling time to AGN outburst (cavity) age across our sample, directly link the presence of star formation and AGN activity in CDGs to cooling instabilities in the intracluster plasma. Our results provide compelling evidence that AGN feedback into the hot ICM is largely responsible for regulating cooling and star formation in the cores of clusters, leading to the significant growth of supermassive black holes in CDGs at late times. 1. INTRODUCTION X-ray observations of the intracluster medium (ICM) in a majority of clusters show stongly peaked central emission from gas with short cooling times (Peres et al. 1998). Such clusters were thought to harbor cooling flows (Fabian 1994), in which gas cooling out of the ICM at the core of the cluster is replaced by gas at larger radii in a slow inward flow. Low-spectral-resolution X-ray observations predicted deposition rates of 100 − 1000's M yr −1 (e.g., Peres et al. 1998). These rates and the implied cold gas masses exceeded the inferred star formation rates (McNamara 1997) and the observed gas masses (Edge 2001) in the central galaxy by an order of magnitude. This apparent disagreement between the amount of gas seen cooling and the amount seen in traditional sinks persisted for more than two decades. Recently, however, high-spectral resolution observations by the Chandra and XMM-Newton X-ray Observatories have shown that the cooling rates predicted by ROSAT are too large by a factor of ten (e.g., David et al. 2001; Blanton et al. 2003; Peterson et al. 2003; Kaastra et al. 2004). These new telescopes have shown that cooling-flow spectra lack the emission signatures expected from …
Wave propagation in a solar quiet region and the influence of the magnetic canopy

Aims. We seek indications or evidence of transmission/conversion of magnetoacoustic waves at the magnetic canopy, as a result of its impact on the properties of the wave field of the photosphere and chromosphere. Methods. We use cross-wavelet analysis to measure phase differences between intensity and Doppler signal oscillations in the Halpha, CaII H, and G-band.We use the height of the magnetic canopy to create appropriate masks to separate internetwork (IN) and magnetic canopy regions. We study wave propagation and differences between these two regions. Results. The magnetic canopy affects wave propagation by lowering the phase differences of progressive waves and allowing the propagation of waves with frequencies lower than the acoustic cut-off. We also find indications in the Doppler signals of Halpha of a response to the acoustic waves at the IN, observed in the CaII H line. This response is affected by the presence of the magnetic canopy. Conclusions. Phase difference analysis indicates the existence of a complicated wave field in the quiet Sun, which is composed of a mixture of progressive and standing waves. There are clear imprints of mode conversion and transmission due to the interaction between the p-modes and small-scale magnetic fields of the network and internetwork.
Dental Researchers' Knowledge About Helsinki Ethical Principles At Mansoura University In Egypt

Objectives: The present study was conducted to assess the knowledge level of dental researchers at Mansoura University of Egypt. Subjects and methods : Participants of this cross-sectional study were recruited from the Faculty of Dentistry at Mansoura University using a well-structured, self-administered, close-ended questionnaire based on the Declaration of Helsinki ethical principles. After providing informed consent, 496 dental researchers participated in the study. Results: Study tool validation revealed content validity indices of 0.88 and 0.86, the internal consistency of the questionnaire items was 0.87. All study participants emphasized the importance of research ethics committees, while 93.5% were aware of the research ethics committee at their institution. The most followed ethical guidelines at the researchers' institutions were the Declaration of Helsinki principles. The participants’ knowledge level about the Declaration was 0.65. Participants' qualifications had the greatest impact on their knowledge level (beta= 0.15 at p = 0.05). Conclusions
Astrophysical black holes in screened modified gravity

Chameleon, environmentally dependent dilaton, and symmetron gravity are three models of modified gravity in which the effects of the additional scalar degree of freedom are screened in dense environments. They have been extensively studied in laboratory, cosmological, and astrophysical contexts. In this paper, we present a preliminary investigation into whether additional constraints can be provided by studying these scalar fields around black holes. By looking at the properties of a static, spherically symmetric black hole, we find that the presence of a non-uniform matter distribution induces a non-constant scalar profile in chameleon and dilaton, but not necessarily symmetron gravity. An order of magnitude estimate shows that the effects of these profiles on in-falling test particles will be sub-leading compared to gravitational waves and hence observationally challenging to detect.
MHD simulations of accretion onto a dipolar magnetosphere - II. Magnetospheric ejections and stellar spin-down

Aims. This paper examines the outflows associated with the interaction of a stellar magnetosphere with an accretion disk. In particular, we investigate the magnetospheric ejections (MEs) due to the expansion and reconnection of the field lines connecting the star with the disk. Our aim is to study the dynamical properties of the outflows and evaluate their impact on the angular momentum evolution of young protostars. Methods. Our models are based on axisymmetric time-dependent magnetohydrodynamic simulations of the interaction of the dipolar magnetosphere of a rotating protostar with a viscous and resistive disk, using alpha prescriptions for the transport coefficients. Our simulations are designed to model the accretion process and the formation of accretion funnels, the periodic inflation/reconnection of the magnetosphere and the associated MEs, and the stellar wind. Results. Similar to a magnetic slingshot, MEs can be powered by the rotation of both the disk and the star so that they can efficiently remove angular momentum from both. Depending on the accretion rate, MEs can extract a relevant fraction of the accretion torque and, together with a weak but non-negligible stellar wind torque, can balance the spin-up due to accretion. When the disk truncation approaches the corotation radius, the system enters a “propeller” regime, where the torques exerted by the disk and the MEs can even balance the spin-up due to the stellar contraction. Conclusions. Magnetospheric ejections can play an important role in the stellar spin evolution. Their spin-down efficiency can be compared to other scenarios, such as the Ghosh & Lamb, X-wind, or stellar wind models. Nevertheless, for all scenarios, an efficient spin-down torque requires a rather strong dipolar component, which has seldom been observed in classical T Tauri stars. A better analysis of the torques acting on the protostar must consider non-axisymmetric and multipolar magnetic components consistent with observations.
Early Education Program Racial and Ethnic Composition and Associations with Quality and Children’s Language and Social-Emotional Development

ABSTRACT This study identified patterns of classroom and family experiences and developmental outcomes for young children in segregated early education. This study is based on data from a high-quality early education program serving young children from low-income households in 19 schools across the U.S. The sample included 1,521 children during the 2016–2017 school year. The analysis examined patterns of association between the racial/ethnic composition of Educare sites and family risk factors, classroom quality, and children’s language and social-emotional performance and growth across the academic year. Research Findings: Findings indicated that although classroom quality, measured through traditional tools, did not vary by school racial/ethnic composition, sociodemographic risk factors, children’s language and social-emotional outcomes did vary by this variable. Practice or Policy: We discuss our results in relation to promotive and inhibitive processed within and outside early education programs, as well as the continued impact of structural equities and lack of culturally responsive pedagogy on children’s learning opportunities and development.
Coulomb Blockade Spectroscopy of a MoS2 Nanotube

Low‐temperature transport spectroscopy measurements on a quantum dot lithographically defined in a multiwall MoS2 nanotube are demonstrated. At T = 300 mK, clear Coulomb blockade is observed, with charging energies in the range of 1 meV. In single‐electron tunneling, discrete conductance resonances are visible at finite bias. Additionally, a magnetic field perpendicular to the nanotube axis reveals clear indications of quantum state transitions, with effective g factors consistent with published theoretical predictions.
COSMIC DUST IN Mg ii ABSORBERS

Mg ii absorbers induce reddening on background quasars. We measure this effect and infer the cosmic density of dust residing in these systems to be Ω ≈ 2 × 10−6, in units of the critical density of the universe, which is comparable to the amount of dust found in galactic disks or about half the amount inferred to exist outside galaxies. We also estimate the neutral hydrogen abundance in Mg ii clouds to be Ω ≈ 1.5 × 10−4, which is approximately 5% of hydrogen in stars in galaxies. This implies a dust-to-gas mass ratio for Mg ii clouds of about 1/100, which is similar to the value for normal galaxies. This would support the hypothesis of the outflow origin of Mg ii clouds, which are intrinsically devoid of stars and hence have no sources of dust. Considerations of the dust abundance imply that the presence of Mg ii absorbers around galaxies lasts effectively for a few Gyr. High-redshift absorbers allow us to measure the rest-frame extinction curve to 900 Å, at which the absorption by the Lyman edge dominates over scattering by dust in the extinction opacity.
IS THE OBSERVED HIGH-FREQUENCY RADIO LUMINOSITY DISTRIBUTION OF QSOs BIMODAL?

The distribution of QSO radio luminosities has long been debated in the literature. Some argue that it is a bimodal distribution, implying that there are two separate QSO populations (normally referred to as “radio-loud” and “radio-quiet”), while others claim it forms a more continuous distribution characteristic of a single population. We use deep observations at 20 GHz to investigate whether the distribution is bimodal at high radio frequencies. Carrying out this study at high radio frequencies has an advantage over previous studies as the radio emission comes predominantly from the core of the active galactic nucleus, and hence probes the most recent activity. Studies carried out at lower frequencies are dominated by the large-scale lobes where the emission is built up over longer timescales (107–108 yr), thereby confusing the sample. Our sample comprises 874 X-ray-selected QSOs that were observed as part of the 6dF Galaxy Survey. Of these, 40% were detected down to a 3σ detection limit of 0.2–0.5 mJy. No evidence of bimodality is seen in either the 20 GHz luminosity distribution or in the distribution of the R20 parameter: the ratio of the radio to optical luminosities traditionally used to classify objects as being either radio-loud or radio-quiet. Previous results have claimed that at low radio luminosities, star formation processes can dominate the radio emission observed in QSOs. We attempt to investigate these claims by stacking the undetected sources at 20 GHz and discuss the limitations in carrying out this analysis. However, if the radio emission was solely due to star formation processes, we calculate that this corresponds to star formation rates ranging from ∼10 M☉ yr−1 to ∼2300 M☉ yr−1.
Dominance of outflowing electric currents on decaparsec to kiloparsec scales in extragalactic jets

Helical magnetic fields embedded in the jets of active galactic nuclei (AGNs) are required by the broad range of theoretical models that advocate for electromagnetic launching of the jets. In most models, the direction of the magnetic field is random, but if the axial field is generated by a Cosmic Battery generated by current in the direction of rotation in the accretion disk, there is a correlation between the directions of the spin of the AGN accretion disk and of the axial field, which leads to a specific direction for the axial electric current, azimuthal magnetic field, and the resulting observed transverse Faraday-rotation (FR) gradient across the jet, due to the systematic change in the line-of-sight magnetic field. We consider new observational evidence for the presence of a nested helical magnetic-field structure such as would be brought about by the operation of the Cosmic Battery, and make predictions about the expected behavior of transverse FR gradients observed on decaparsec and kiloparsec scales. The collected results can be understood if the dominant azimuthal field on parsec scales corresponds to an axial electric current flowing inward along the jet, whereas the (weaker) dominant azimuthal field on kiloparsec scales corresponds to a outward-flowing current in the outer sheath of the jet and/or an extended disk wind.
DERIVING STELLAR INCLINATION OF SLOW ROTATORS USING STELLAR ACTIVITY

Stellar inclination is an important parameter for many astrophysical studies. Although different techniques allow us to estimate stellar inclination for fast rotators, it becomes much more difficult when stars are rotating slower than ∼2–2.5 km s−1. By using the new activity simulation SOAP 2.0 which can reproduce the photometric and spectroscopic variations induced by stellar activity, we are able to fit observations of solar-type stars and derive their inclination. For HD 189733, we estimate the stellar inclination to be deg, which implies a star–planet obliquity of considering previous measurements of the spin–orbit angle. For α Cen B, we derive an inclination of , which implies that the rotational spin of the star is not aligned with the orbital spin of the α Cen binary system. In addition, assuming that α Cen Bb is aligned with its host star, no transit would occur. The inclination of α Cen B can be measured using 40 radial-velocity measurements, which is remarkable given that the projected rotational velocity of the star is smaller than 1.15 km s−1.
A new RASS galaxy cluster catalogue with low contamination extending to z ∼ 1 in the DES overlap region

We present the MARD-Y3 catalogue of between 1086 and 2171 galaxy clusters (52 per cent and 65 per cent new) produced using multicomponent matched filter (MCMF) follow-up in 5000 deg2 of DES-Y3 optical data of the ∼20 000 overlapping ROSAT All-Sky Survey source catalogue (2RXS) X-ray sources. Optical counterparts are identified as peaks in galaxy richness as a function of redshift along the line of sight towards each 2RXS source within a search region informed by an X-ray prior. All peaks are assigned a probability fcont of being a random superposition. The clusters lie at 0.02 < z < 1.1 with more than 100 clusters at z > 0.5. Residual contamination is 2.6 per cent and 9.6 per cent for the cuts adopted here. For each cluster we present the optical centre, redshift, rest frame X-ray luminosity, M500 mass, coincidence with NWAY infrared sources, and estimators of dynamical state. About 2 per cent of MARD-Y3 clusters have multiple possible counterparts, the photo-z’s are high quality with σΔz/(1 + z) = 0.0046, and ∼1 per cent of clusters exhibit evidence of X-ray luminosity boosting from emission by cluster active galactic nuclei. Comparison with other catalogues (MCXC, RM, SPT-SZ, Planck) is performed to test consistency of richness, luminosity, and mass estimates. We measure the MARD-Y3 X-ray luminosity function and compare it to the expectation from a fiducial cosmology and externally calibrated luminosity- and richness–mass relations. Agreement is good, providing evidence that MARD-Y3 has low contamination and can be understood as a simple two step selection – X-ray and then optical – of an underlying cluster population described by the halo mass function.
Searching in the dark: the dark mass content of the Milky Way globular clusters NGC288 and NGC6218

We present an observational estimate of the fraction and distribution of dark mass in the innermost region of the two Galactic globular clusters NGC 6218 (M12) and NGC 288. Such an assessment has been made by comparing the dynamical and luminous mass profiles derived from an accurate analysis of the most extensive spectroscopic and photometric surveys performed on these stellar systems. We find that non-luminous matter constitutes more than 60% of the total mass in the region probed by our data (R<1.6 arcmin~r_h) in both clusters. We have carefully analyzed the effects of binaries and tidal heating on our estimate and ruled out the possibility that our result is a spurious consequence of these effects. The dark component appears to be more concentrated than the most massive stars suggesting that it is likely composed of dark remnants segregated in the cluster core.
MULTIPLE STELLAR POPULATIONS IN THE GALACTIC GLOBULAR CLUSTER NGC 6752

We have carried out high-precision photometry on a large number of archival Hubble Space Telescope images of the Galactic globular cluster NGC 6752, to search for signs of multiple stellar populations. We find a broadened main sequence (MS) and demonstrate that this broadening cannot be attributed either to binaries or to photometric errors. There is also some indication of an MS split. No significant spread could be found along the sub-giant branch, however. Ground-based photometry reveals that in the U versus (U − B) color–magnitude diagram the red-giant branch (RGB) exhibits a clear color spread, which we have been able to correlate with variations in Na and O abundances. In particular, the Na-rich, O-poor stars identified by Carretta et al. define a sequence on the red side of the RGB, while Na-poor, O-rich stars populate a bluer, more dispersed portion of the RGB.
Observation of quantum diffractive collisions using shallow atomic traps

We present measurements and calculations of the trap loss rate for laser-cooled $^{87}\text{R}\text{b}$ atoms confined in either a magneto-optic trap (MOT) or a magnetic quadrupole trap when exposed to a room-temperature background gas of Ar. We study the loss rate as a function of trap depth and find that copious glancing elastic collisions, which occur in the so-called quantum diffractive regime and impart very little energy to the trapped atoms, result in significant differences in the loss rate for the MOT compared to a pure magnetic trap due solely to the difference in potential depth. This finding highlights the importance of knowing the trap depth when attempting to infer the total collision cross section from measurements of trap loss rates. Moreover, this variation in trap loss rate with trap depth can be used to extract information about the differential cross section.
The properties of a large volume-limited sample of face-on low surface brightness disk galaxies

We select a large volume-limited sample of low surface brightness galaxies (LSBGs, 2021) to investigate in detail their statistical properties and their differences from high surface brightness galaxies (HSBGs, 3639). The distributions of stellar masses of LSBGs and HSBGs are nearly the same and they have the same median values. Thus this volume-limited sample has good completeness and is further removed from the effect of stellar masses on their other properties when we compare LSBGs to HSBGs. We found that LSBGs tend to have lower stellar metallicities and lower effective dust attenuations, indicating that they have lower dust than HSBGs. The LSBGs have relatively higher stellar mass-to-light ratios, higher gas fractions, lower star forming rates (SFRs), and lower specific SFRs than HSBGs. Moreover, with the decreasing surface brightness, gas fraction increases, but the SFRs and specific SFRs decrease rapidly for the sample galaxies. This could mean that the star formation histories between LSBGs and HSBGs are different, and HSBGs may have stronger star forming activities than LSBGs.
Frequency of Maxillofacial Bone and Cartilage Tumors in Cairo Governorate: A Retrospective Multi-centered Study

Aim: The aim of this study was to identify the prevalence of the primary non-odontogenic maxillofacial bone and cartilage tumors. Methodology: Clinical data and histopathological diagnoses of primary non-odontogenic maxillofacial bone and cartilage tumors, diagnosed between January 2010 and December 2019, were collected from the histopathological reports of Cairo governorate’s educational hospitals and institutions. Results: Out of 11,444 archival reports -found in the maxillofacial bones and paranasal sinuses- collected from the mentioned study centers, 186 were reported as non-odontogenic maxillofacial bone and cartilage tumors, yielding a 1.63% prevalence. Osteosarcoma was the most common lesion, followed by chondrosarcoma and osteoma, respectively. Females were found to be more prone to the investigated tumors. Conclusion: The non-odontogenic maxillofacial bone and cartilage tumors represent 1.63% in Cairo governorate. Demographic variations were seen in some of the tumors studied, which differed from the literature; however, osteosarcoma was found to be the most prevalent lesion, accounting for over half of the lesions studied.
Dust in the interplanetary medium

The mass density of dust particles that form from asteroids and comets in the interplanetary medium of the solar system is, near 1 AU, comparable to the mass density of the solar wind. It is mainly contained in particles of micrometer size and larger. Dust and larger objects are destroyed by collisions and sublimation and hence feed heavy ions into the solar wind and the solar corona. Small dust particles are present in large number and as a result of their large charge to mass ratio deflected by electromagnetic forces in the solar wind. For nanodust particles of sizes ≃1–10 nm, recent calculations show trapping near the Sun and outside from about 0.15 AU ejection with velocities close to solar wind velocity. The fluxes of ejected nanodust are detected near 1 AU with the plasma wave instrument onboard the STEREO spacecraft. Although such electric signals have been observed during dust impacts before, the interpretation depends on several different parameters and data analysis is still in progress.