adsabs/FOCAL huggingface dataset:
To perform a statistical analysis of the average quiescent fraction of satellites around our sample of massive galaxies, we use a statistical background subtraction technique (e.g., Kauffmann et al. 2010; Tal et al. 2012; Wang & White 2012; Kawinwanichakij et al. 2014). We detect objects within fixed apertures centered on our central galaxies and satisfying Equation (2). These apertures include physically associated galaxies as well as chance alignments of foreground and background galaxies. We estimate and correct for the contamination due to chance alignments by placing random apertures across the field. We adapt this procedure by restricting the placement of the random apertures to regions near the centrals, as demonstrated by Chen et al. (2006). This accounts for the bias due to contaminating galaxies that are physically associated with the centrals but are not satellites (i.e., the 2-halo term of the correlation function; see Chen et al. 2006).15

15
The contaminating galaxies that are physically associated with the central galaxies in our sample are expected to have marginally different properties than truly random field galaxies due to the fact that they exist in biased regions of the universe. There may be an additional effect due to large-scale 2-halo conformity. If 2-halo conformity exists, our procedure effectively corrects for it.
 We therefore place the random apertures within annuli with inner and outer radii equal to 1 and 3 cMpc from each central galaxy for the UDS and UltraVISTA. Parenthetically, our tests showed that the restriction on the location of the background apertures has only a small effect on the conformity signal. Relative to apertures that are placed randomly through the field, this correction increases the quiescent fractions of background galaxies by 0.4%–10%. For the smaller ZFOURGE fields, placing the random apertures within annuli is too restrictive, and for this survey we randomly place the apertures across the fields. We do note that the ZFOURGE fields are small enough that even these randomly placed apertures trace the same large-scale environment as the centrals. Additionally, we find that when we restrict the background apertures to be 





 cMpc from the centrals, it changes the measured quenching efficiencies (see Section 4 below) by 10%, and none of our conclusions would be changed.
Citation: Chen et al. (2006)
Citation function: Uses
Studying the dynamical properties of rotating neutron stars is a domain which brings out various interesting features when one assumes a perfect fluid. It is known that the centrifugal force of a rotating star counters gravitational force and hence one can expect massive stars to be fast rotors, at least in the initial stages of the stellar evolution. As a result of rotation a star may experience damping due to unstable oscillations such as the r-modes. The r-modes are one of many pulsating modes that exist in neutron stars and are characterized by the Coriolis force acting as the restoring force (Andersson 1998). The r-modes are unstable to emission of gravitational radiation (GR) by the Chandrashekhar-Friedman-Schutz (CFS) mechanism (Chandrasekhar 1970; Friedman & Schutz 1978). It was shown in Andersson (1998) that the r-modes are unstable for all rotating perfect fluid stars irrespective of their frequency. Dissipative effects such as shear and bulk viscosities work towards suppressing GR driven instabilities and has been studied by various authors over the past few years (Lindblom, Owen & Morsink 1998; Jones 2001; Lindblom & Owen 2002; van Dalen & Dieperink 2004; Drago, Lavagno & Pagliara 2005; Nayyar & Owen 2006; Jaikumar, Rupak & Steiner 2008; Jha, Mishra & Sreekanth 2010; Ofengeim et al. 2019) under various considerations. If the GR time-scale is shorter than the damping time-scale due to such dissipative processes, then the r-mode will be unstable and a rapidly rotating neutron star could lose a significant fraction of its rotational energy through GR. At higher temperatures (T > 109 K), the dominant dissipation is due to bulk viscosity, which arises due to density and pressure perturbations, a consequence of the star being driven out of equilibrium by oscillations. The system tries to restore equilibrium through various internal processes. In the case of r-modes, since the typical frequencies are of the order of the rotational frequencies of the stars, the reactions that dominate are the weak processes. Within these weak processes, although the modified Urca processes involving leptons are important, it has been shown that non-leptonic processes involving hyperons contribute more significantly towards bulk viscosity at temperatures lower than a few times 109 K (Lindblom & Owen 2002). Our goal here is to investigate the same using a chiral model calibrated to reproduce the desired nuclear matter properties, in particular the density content of the nuclear symmetry energy at both low and high densities.
Citation: Jones 2001
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Using the whole sample (\hbox{$\bar{z}=0.40$}z̅ = 0.40), we find a decreasing faint end for both datasets with consistent values between HST (α =  − 0.76 ± 0.07) and Subaru (α =  − 0.78 ± 0.06). Separating between low-redshift (\hbox{$\bar{z}=0.29$}z̅ = 0.29) and high-redshift (\hbox{$\bar{z}=0.51$}z̅ = 0.51) samples, we find an evolution of the faint end slope of 1.7σ with HST and 2.6σ with Subaru. There is thus a mild decrease of the faint end slope (less negative α) with increasing redshift over the range (0.187 z 0.686). This evolution is in good agreement with recent papers in the literature: in particular Zenteno et al. (2016) found a decrease of the RS faint end at 2.1σ for a wider range of redshifts (0.1 z 1.13), but with ~ 80% of their clusters being in the same redshift range as ours. De Propris et al. (2013) claim that the evolution in the faint end slope has a significant contribution from surface brightness selection effects. They used HST data of differing depths on a single cluster (MS 1358.4+6254) to show that surface brightness selection effects become important above the formal magnitude limit of their data and that they affect the RS GLF at magnitudes z ≥ 24.5 for 2.7 ks HST exposures (see their Fig. 18). The faint RS for their cluster has F814W − z = 0.25, implying that the SB selection effects in their sample become important at F814W> 24.75. On the other hand, our CLASH data are significantly deeper than theirs (4.1 ks) and we limit our GLFs at F814W 24.5. Therefore, the real SB selection effects noticed in De Propris et al. (2013) should not be playing a role in our space-based results. In addition, De Propris et al. (2013) claim that previous estimates of the evolution in the RS GLF (e.g.,  De Lucia et al. 2007; Rudnick et al. 2009) were also due to SB effects. Both of those works were based on the same ground-based data with a formal magnitude limit of I = 24 or 24.5 (for the low- and high-redshift clusters, respectively) and the evolution in the GLF was seen over the faintest 2 mag. We cannot directly address the role of SB effects in the EDisCS results without detailed simulations on those data (see below for such simulations for our clusters) but the similarity between our HST and Subaru GLFs imply that the EDisCS evolution in the GLF is not dominated by SB effects.
Citation: De Propris et al. (2013)
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Citation: De Propris et al. (2013)
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To measure the emission lines’ flux within a spectrum, it is essential to fit the lines using the proper model with parameters that allow us to represent the intensities in all spectral elements. Estimating the number of components of each underlying emission line (i.e., multiple lines with multiple velocity components as would be expected from merging galaxy systems) is also crucial to extract meaningful information from the lines. Standard methodologies require fitting both single and double component models and computing their Bayes factors, or approximating it using a proxy such as the Akaike (or Bayesian) information criterion (AIC; Rhea et al. 2020b). However, these methods are highly reliant on the accuracy of the fits (e.g., Kieseppä 1997; Pooley & Marion 2018). Several promising new methods have been proposed utilizing machine-learning algorithms to solve this problem (Hampton et al. 2017; Keown et al. 2019; Rhea et al. 2020a). In particular, CLOVER, developed in Keown et al. (2019), uses a convolutional neural network (CNN) to classify high-resolution radio emission lines as having either single or double underlying components. In this paper, we expand upon this methodology for medium resolution, Fourier Transform IFU spectra taken by the Spectromètre Imageur à Transformée de Fourier pour l’Etude en Long et en Large de raies d’Emission (SITELLE) instrument at the Canada–France–Hawai’i Telescope (Baril et al. 2016). Each SITELLE observation contains approximately 4 million pixels and, thus, produces 4 million spectra of a given resolution set by the principal investigator (1  R  10, 000; Drissen et al. 2014; Martin & Drissen 2017; Drissen et al. 2019). The instrumental line function of SITELLE is described as a sinc model convolved with a Gaussian to represent intrinsic line broadening, which requires special care during the fitting process (Martin et al. 2016). Therefore, the development of machine-learning applications for SITELLE demands special treatment of the underlying emission profiles.
Citation: Rhea et al. 2020b
Citation function: Background
Similarly, there is general agreement about the astrophysical effects responsible for velocity segregation between more and less luminous galaxies. This effect can be explained by physical processes such as dynamical friction (also called dynamical breaking) that cause transfers of kinetic energy from larger galaxies to smaller galaxies, as well as gravitational interactions that can convert bulk kinetic energy into internal kinetic energy via, for example, accelerating and ejecting individual stars during galaxy mergers (Sarazin 1986; Kashlinsky 1987; Biviano et al. 1992; Mahajan et al. 2011). It is mildly puzzling that the velocity segregation effect that we see in our data for the brightest and faintest galaxies does not appear in some recent simulations; we are not the first to detect this signal in bright cluster member galaxies, (Chincarini & Rood 1977; Biviano et al. 1992; Mohr et al. 1996; Goto 2005; Ribeiro et al. 2010; Old et al. 2013; Barsanti et al. 2016), and the effect is seen in some simulations (e.g., Lau et al. 2010; Saro et al. 2013). We are wary of over-interpreting this discrepancy, because of the difference in our bright galaxy sample and the 50 brightest members approach used by Gifford et al. (2013), but it is possible that the discrepancy is related to the effects of missing baryonic/gas physics that are not captured in dark matter only simulations. We elect not to speculate too much about the pros and cons of various methods for the treatment of halos in simulated clusters, and how mock galaxies are placed into those halos, though it is not unreasonable to suppose that different prescriptions could generate significantly different results. Certainly the measurement we present here could represent a useful benchmark test to be reproduced in future simulations. Looking forward, we believe it is important that both observers and simulators strive to find useful quantities that can be measured in both data and simulations; it is with this in mind that we analyze galaxies in our sample in terms of relative luminosity, scaled by the characteristic magnitude, m*.
Citation: Ribeiro et al. 2010
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Several models have been advanced to explain the obliquity dichotomy, but so far none can account for all the relevant observations. Interpretations based solely on differences in the stellar properties (e.g., Rogers et al. 2012) cannot address the inferred dependence of the obliquity on Mp and the detection of highly misaligned planets around cool stars. In view of the fact that 





 corresponds to the temperature above which the size of the outer convective zone of a main-sequence (MS) F star shrinks rapidly, it was suggested that close-in planets in both cool and hot stars are initially distributed over the entire angular range (0°–180°), but that only in cool stars where a substantial convective envelope is present can a sufficiently massive close-in planet (





) realign the star through tidal interaction (e.g., Winn et al. 2010; Albrecht et al. 2012). The host stars are also subject to magnetic braking, which declines strongly above the same transition temperature (corresponding to the break in the Kraft curve; Kraft 1967), and it was argued (Dawson 2014) that this, rather than the tidal dissipation efficiency, is the main factor underlying the difference in obliquity properties between cool and hot stars. Both variants of this scenario, however, face the conundrum that an HJ undergoing equilibrium tidal interaction with its host star would spiral in and be ingested on a timescale that is comparable to the realignment time. A possible way out of this difficulty is to appeal to the {10} component of the dynamical tide, which could in principle significantly reduce the alignment time without affecting the ingestion time (Lai 2012).1

1
An alternative possibility, that only the outer convective layer (Winn et al. 2010)—or even just a part of it (Dawson 2014)—partakes in the realignment process, is hard to justify on either theoretical or observational grounds.
 However, even though this model can be used to account for individual systems (Valsecchi & Rasio 2014), it remains unclear whether it can explain the overall λ distribution of HJs and the manifested difference between cool and hot stars (Rogers & Lin 2013; Xue et al. 2014). Furthermore, even the basic tidal interaction interpretation of the obliquity dichotomy has now been called into question by the results of Mazeh et al. (2015), who analyzed the rotational photometric modulations of a large sample of Kepler sources and inferred that (1) the conclusion that planets around cool stars are well aligned, and those around hot stars are not, is general and not restricted just to HJs; and (2) the low obliquity of planets around cool stars extends to orbital periods Porb that are a factor of ∼10 larger than the maximum value (





 days) for robust tidal interaction between an HJ and a 





 Gyr old G or F star.
Citation: Kraft 1967
Citation function: Background
The above analysis addresses a number of open questions. Firstly, it is necessary to ask whether impulsive heating events, such as Ohmic dissipation associated with magnetic field braiding can trigger coronal rain formation in the first place. The evolution of loop L1 shows that this is indeed possible, as the duration of the impulsive heating events occuring in the loop is 100−200 s, similar to the loop radiative cooling timescale of ∼100 s. An impulsive heating event of significant amplitude and with duration that is comparable to the radiative cooling timescale is sufficient to cause sufficient chromospheric evaporation into the loop for the loop to become thermally unstable (Johnston et al. 2019). Previous studies that addressed prominence formation with using a time-variable coronal heating term found that formation of condensations still occurs if 1. the heating is intermittent, but the frequency of the individual heating events exceeds the inverse of the radiative cooling timescale (Karpen & Antiochos 2008) and 2. if the heating ceases during the condensation formation, the condensation still continues to grow (Xia et al. 2011). It should also be noted that such impulsive events can also act as a perturbation that trigger the catastrophic cooling in a marginally stable plasma. We noted differences between condensations formed in loops L1 and L2, in particular that the heating driving the condensation formation in L1 has an impulsive character compared to the gradual heating of L2. Also, the cooling timescale of the condensation formed in L1 is much shorter than that of the condensation formed along L2, suggesting different conditions at coronal heights. Secondly, we also addressed the issue of the apparent coronal rain formation along open field lines and shown that flows of evaporated plasma can lead to sufficient density increase to trigger radiative instability in both closed and open magnetic field configurations. Finally, our work also addresses a possible mechanism responsible for destruction of coronal rain condensations before they reach the solar surface. A reconnection event occurring in the upper part of the leg of loop 3 leads to the condensation being heated to very high temperatures and subsequently destroyed as a result. This suggests that the lifetime of the condensations can be dependent on the frequency of such reconnection events in shorter loops. Also, it might possibly explain why coronal rain is not observed in short low-lying loops close to the active region core that are heated to very high temperatures. Even if the condensations do form in such loops (which is significantly less likely as it is easier to trigger thermal instability in longer loops; see e.g. Müller et al. 2004, 2005), they are most likely short-lived.
Citation: Johnston et al. 2019
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This work focuses on the formation of systems with high mass ratios and component masses in the LMG through canonical isolated binary evolution. Many other channels have been proposed for producing the compact binary mergers observed by LIGO–Virgo. Dynamical formation in dense stellar clusters such as globular clusters preferentially produces compact binaries with similar masses (e.g., Sigurdsson & Hernquist 1993), and thus the formation of NSBHs and other compact binaries with highly asymmetric masses is predicted to be rare (Clausen et al. 2013; Arca Sedda et al. 2020; Ye et al. 2020). While hierarchical mergers of NSs have been proposed as a means of populating the LMG (Gupta et al. 2020), this scenario is unlikely since heavier BHs dominate the dynamical interactions in clusters (e.g., Samsing & Hotokezaka 2020; Ye et al. 2020). The formation of compact binaries with highly asymmetric masses may be more prevalent in young star clusters (e.g., di Carlo et al. 2019; Rastello et al. 2020; Santoliquido et al. 2020), but Fragione & Banerjee (2020) finds the merger rate of NSBH systems in young massive and open clusters to be three orders of magnitude lower, similar to the predictions from old globular clusters. Other formation mechanisms have been explored for forming highly asymmetric compact binary mergers and mergers with components in the LMG, such as hierarchical systems in the galactic field (e.g., Antonini et al. 2017; Silsbee & Tremaine 2017; Fragione & Kocsis 2019; Safarzadeh et al. 2019; Fragione et al. 2020), hierarchical systems in galactic nuclei with a supermassive BH as the outer perturber (e.g., Antonini & Perets 2012; Petrovich & Antonini 2017; Hoang et al. 2018; Fragione et al. 2019; Stephan et al. 2019), and in disks around supermassive BHs in active galactic nuclei (e.g., McKernan et al. 2019; Yang et al. 2019). However, the rates and formation properties from these channels are uncertain. Nevertheless, a full picture of compact-binary mergers will require consideration of all these channels and investigation of how physical prescriptions (such as the connection between the underlying SN mechanism and remnant mass) jointly affect population properties, rates, and branching ratios across these channels (e.g., Stevenson et al. 2017; Talbot & Thrane 2017; Vitale et al. 2017; Zevin et al. 2017; Arca Sedda et al. 2020). The identification of bona fide NSBH systems and other compact-binary mergers with highly asymmetric masses will further constrain the relative contribution of various formation channels and the underlying physics of these formation pathways.
Citation: Santoliquido et al. 2020
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Recent years have seen a burgeoning in the volume of spatially resolved spectroscopic data from large surveys such as CALIFA (Sánchez et al. 2012), SAMI (Croom et al. 2012), and MaNGA (Bundy et al. 2015). These data have stimulated interest in the relationship between the gas-phase oxygen abundances, stellar mass, star formation rate (SFR), and gas content of galaxies on kiloparsec scales (e.g., Barrera-Ballesteros et al. 2016, 2018; Mingozzi et al. 2020; Teklu et al. 2020; Wang & Lilly 2021). By analogy to the global mass–metallicity relation (Tremonti et al. 2004), the oxygen abundance has been shown to be sensitive to the local stellar mass surface density (Σ*), tracing the integrated star formation history on local scales in a galaxy, as well as the presence of outflows (e.g., Barrera-Ballesteros et al. 2018) and inflows (Lian et al. 2019; Schaefer et al. 2019). Since early observations of this local relationship between Σ* and 12+log(O/H) (Moran et al. 2012; Rosales-Ortega et al. 2012), there has been a growing consensus that the global mass–metallicity relation can be explained as arising on local scales. That is, the accumulation of chemical elements on kiloparsec scales can be seen as a reflection of the buildup of stellar mass locally within galaxies over their evolutionary history rather than on global scales (see, e.g., Sánchez 2020; Sánchez et al. 2021). This is reinforced by recent observations that gas-phase chemical abundances in galaxies are correlated on ∼kiloparsec scales (Sánchez et al. 2015; Kreckel et al. 2020; Li et al. 2021), implying that their chemical enrichment proceeds by the local injection and diffusion of metals into the interstellar medium (ISM) of galaxies. Nevertheless, some observations have shown that the local gas-phase metallicity is also related to the total stellar mass of galaxies (Gao et al. 2018). This is likely due to the greater depth of the gravitational potential well of more massive galaxies, which makes the expulsion of metals through feedback-driven outflows more difficult.
Citation: Tremonti et al. 2004
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