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Context. Near open clusters as Pleiades, Praesepe and Blanco 1 have been extensively studied due to their proximity to the Sun.
The evolution of differential ages of passive galaxies at different redshifts (cosmic chronometers) has been proved to be a method potentially able to constrain the Hubble parameter in a cosmology-independent way, but the systematic uncertainties must be carefully evaluated. In this paper, we compute the contribution ...
FN Tau is a rare example of very low-mass T Tauri stars that exhibits a spatially resolved nebulosity in near-infrared scattering light. To directly derive the parameters of a circumstellar disk around FN Tau, observations of dust continuum emission at 340 GHz are carried out with the Submillimeter Array (SMA).
We present results from a survey of the internal kinematics of 49 star-forming galaxies at z$\,\sim\,$2 in the CANDELS fields with the Keck/MOSFIRE spectrograph (SIGMA, Survey in the near-Infrared of Galaxies with Multiple position Angles). Kinematics (rotation velocity $V_{rot}$ and integrated gas velocity dispersion...
Supermassive black holes can capture or disrupt stars that come sufficiently close. This article reviews the dynamical processes by which stars or stellar remnants are placed onto loss-cone orbits and the implications for feeding rates.
We derive two-dimensional spatial power spectra of four distinct interstellar medium tracers, HI, $^{12}$CO($J$=1--0), $^{13}$CO($J$=1--0), and dust, in the Perseus molecular cloud, covering linear scales ranging from $\sim$0.1 pc to $\sim$90 pc. Among the four tracers, we find the steepest slopes of $-3.23\pm0.05$ an...
The dense central regions of tidally disrupted galaxies can survive as ultra-compact dwarfs (UCDs) that hide among the luminous globular clusters (GCs) in the halo of massive galaxies. An exciting confirmation of this model is the detection of overmassive black holes in the centers of some UCDs, which also lead to ele...
We present colour-magnitude diagrams (CMDs) for a sample of seven young massive clusters in the galaxies NGC 1313, NGC 1569, NGC 1705, NGC 5236 and NGC 7793. The clusters have ages in the range 5-50 million years and masses of 10^5 -10^6 Msun.
We discuss the construction of the Galaxy And Mass Assembly (GAMA) 10h region (G10) using publicly available data in the Cosmic Evolution Survey region (COSMOS) in order to extend the GAMA survey to z~1 in a single ~1 deg^2 field. In order to obtain the maximum number of high precision spectroscopic redshifts we re-re...
AGN driven outflows are invoked in numerical simulations to reproduce several observed properties of local galaxies. The z > 1 epoch is of particular interest as it was during this time that the volume averaged star formation and the accretion rate of black holes were maximum.
We present the results of the HIGHz Arecibo survey, which measured the HI content of 39 galaxies at redshift $z>0.16$ selected from the Sloan Digital Sky Survey. These are all actively star-forming, disk-dominated systems in relatively isolated environments, with stellar and HI masses larger than $10^{10}$ M$_\odot...
We have performed CO J =1-0 observations of ten galaxies hosting luminous ($L_{\rm bol} > 10^{46}\,{\rm erg\,s^{-1}}$) type 1 active galactic nuclei (AGNs) with the Nobeyama 45-m radio telescope. The targets are selected because they are expected to be rich in molecular gas based on their high nebular dust extincti...
We report deep optical integral-field spectroscopy with the MUSE of the luminous radio-quiet QSO PG1307+085 (z=0.154) obtained during the commissioning of the instrument. Given the high sensitivity and spatial resolution delivered by MUSE, we are able to resolve the compact ($r_e$~1.3") elliptical host galaxy.
The intracluster light (ICL) is a luminous component of galaxy clusters composed of stars that are gravitationally bound to the cluster potential but do not belong to the individual galaxies. Previous studies of the ICL have shown that its formation and evolution are intimately linked to the evolutionary stage of the ...
Previous observations have revealed an accretion disk and outflow motion in high-mass star-forming region G192.16-3.84. While collapse have not been reported before.
We report the detection in IRC+10216 of lines of HNC $J$=3-2 pertaining to 9 excited vibrational states with energies up to $\sim$5300 K. The spectrum, observed with ALMA, also shows a surprising large number of narrow, unidentified lines that arise in the vicinity of the star. The HNC data are interpreted through a 1...
Nuclear star clusters (NSCs) are dense star clusters located at the centre of galaxies spanning a wide range of masses and morphologies. Analysing NSC occupation statistics in different environments provides an invaluable window into investigating early conditions of high-density star formation and mass assembly in cl...
Context. We investigate the binding energies of atoms to interstellar dust particles, which play a key role in their growth and evolution, as well as for the chemical reactions on their surfaces.
We present new observations of sixteen bright ($r=19-21$) gravitationally lensed galaxies at $z\simeq 1-3$ selected from the CASSOWARY survey. Included in our sample is the $z=1.42$ galaxy CSWA-141, one of the brightest known reionization-era analogs at high redshift (g=20.5), with a large sSFR (31.2 Gyr$^{-1}$) and a...
We present the results of deep, high-resolution, 5 GHz Expanded Very Large Array (EVLA) observations of the nearby, dwarf lenticular galaxy and intermediate mass black hole candidate (M ~4.5 x 10^5 M_sun), NGC 404. For the first time, radio emission at frequencies above 1.4 GHz has been detected in this galaxy.
Dwarf Galaxies are the most common objects in the Universe and are believed to contain large amounts of dark matter. There are mainly three morphologic types of dwarf galaxies: dwarf ellipticals, dwarf spheroidals and dwarf irregulars.
Theoretical works have shown that off-plane motions of bars can heat stars in the vertical direction during buckling but is not clear how do they affect the rest of components of the Stellar Velocity Ellipsoid (SVE). We study the 2D spatial distribution of the vertical, $\sigma_{z}$, azimuthal, $\sigma_{\phi}$ and rad...
We point out an anti-correlation between the central dark matter (DM) densities of the bright Milky Way dwarf spheroidal galaxies (dSphs) and their orbital pericenter distances inferred from Gaia data. The dSphs that have not come close to the Milky Way center (like Fornax, Carina and Sextans) are less dense in DM tha...
We present a simple model for the host mass dependence of the galaxy nucleation fraction ($f_{nuc}$), the galaxy's nuclear star cluster (NSC) mass and the mass in its surviving globular clusters ($M_{GC,obs}$). Considering the mass and orbital evolution of a GC in a galaxy potential, we define a critical mass limi...
The peptide-like molecules, cyanoformamide (NCCONH2), is the cyano (CN) derivative of formamide (NH2CHO). It is known to play a role in the synthesis of nucleic acid precursors under prebiotic conditions.
We present ASteCA (Automated Stellar Cluster Analysis), a suit of tools designed to fully automatize the standard tests applied on stellar clusters to determine their basic parameters. The set of functions included in the code make use of positional and photometric data to obtain precise and objective values for a giv...
We present N-body simulations of the process of bulge formation in disc galaxies due to inward migration of massive stellar clumps. The process is accompanied by dark halo heating, with a quasi-isothermal core replacing the initial central density cusp, transforming an initially dark matter dominated central region in...
The distribution of hot interstellar medium in early-type galaxies bears the imprint of the various astrophysical processes it underwent during its evolution. The X-ray observations of these galaxies have identified various structural features related to AGN and stellar feedback and environmental effects such as mergi...
Only recently, complex models that include the global dynamics from dwarf satellite galaxies, dark matter halo structure, gas infalls, and stellar disk in a cosmological context became available to study the dynamics of disk galaxies such as the Milky Way (MW). We use a MW model from a high-resolution hydrodynamical c...
The occurrence of complex organic molecules (COMs) in the gas phase at low temperature in the dense phases of the ISM suggests that a non-thermal desorption mechanism is at work because otherwise, COMs should condense within a short timescale onto dust grains. Vacuum ultraviolet photodesorption has been shown to be mu...
Following the established view of the AGNs inner workings, an AGN is radio-loud (RL) if associated with relativistic ejections emitting a radio synchrotron spectrum (i.e., a jetted AGN). If large samples of optically-selected quasars are considered, AGNs are identified as RL if their Kellermann's radio loudness ra...
We collected the archival data of blazar OJ~287 from heterogeneous very long baseline interferometry (VLBI) monitoring programs at 2.3 GHz, 8.6 GHz, 15 GHz and 43 GHz. The data reduction and observable extraction of those multi-band multi-epoch observations are batch-processed consistently with our automated pipeline....
We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted onto BHs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on BH growth.
It is exceedingly rare to find quiescent low-mass galaxies in the field. UGC5205 is an example of such a quenched field dwarf ($M_\star\sim3\times10^8M_\odot$).
We combine the Dark Energy Camera Legacy Survey (DECaLS) DR8 photometry with Gaia photometry to study the 3-D structure of Bootes I, Draco, Ursa Minor, Sextans and Sculptor dwarf galaxies using blue horizontal branch (BHB) stars as distance indicators. We construct a new colour-absolute magnitude of BHB stars that we ...
We present ~1" resolution (~2 kpc in the source plane) observations of the CO(1-0), CO(3-2), Halpha, and [N II] lines in the strongly-lensed z=2.26 star-forming galaxy SDSS J0901+1814. We use these observations to constrain the lensing potential of a foreground group of galaxies, and our source-plane reconstructio...
Many theoretical and observational studies have suggested that galaxy mergers may trigger enhanced star formation or active galactic nuclei (AGN) activity. We present an analysis of merging and nonmerging galaxies from $0.2 \leq z \leq 3$ in the IllustrisTNG50 simulation.
We report discoveries of 165 new quasar Ca II absorbers from the Sloan Digital Sky Survey (SDSS) Data Release 7 and 12. Our Ca II rest frame equivalent width distribution supports the weak and strong subpopulations, split at ${W}^{\lambda3934}_{0}=0.7$Å.
We report the first detection of the isotopologues 13CCC and C13CC. We used the heterodyne receivers GREAT and upGREAT on board SOFIA to search for the ro-vibrational transitions Q(2) and Q(4) of 13CCC and C13CC at 1.9 THz along the line of sight towards SgrB2(M).
We use a robust analytical model together with a high-resolution hydrodynamical cosmological simulation to demonstrate that in a $\Lambda$ cold dark matter ($\Lambda$CDM) universe, a small fraction of dwarf galaxies inhabiting dark matter (DM) halos in the mass range $3\times 10^{9} \lesssim M_{200} / M_{\odot} \lesssi...
The James Webb Space Telescope will provide observational capabilities that far exceed those of current ground- or space-based instrumentation. In particular, the NIRSpec instrument will take highly sensitive spectroscopic data for hundreds of objects simultaneously from 0.6-5.3 microns.
By comparing Cepheid brightnesses with geometric distance measures including Gaia EDR3 parallaxes, most recent analyses conclude metal-rich Cepheids are brighter, quantified as $\gamma \sim -0.2$ mag/dex. While the value of $\gamma$ has little impact on the determination of the Hubble constant in contemporary distance...
We study the structure, age and metallicity gradients, and dynamical evolution using a cosmological zoom-in simulation of a Milky Way-mass galaxy from the Feedback in Realistic Environments project. In the simulation, stars older than 6 Gyr were formed in a chaotic, bursty mode and have the largest vertical scale heig...
This paper presents the spatially resolved star formation history (2D-SFH) of a small sample of four local mergers: the early-stage mergers IC1623, NGC6090, and the Mice, and the more advanced merger NGC2623, by analyzing IFS data from the CALIFA survey and PMAS in LArr mode. Full spectral fitting techniques are appli...
The radio-loud quasar CTD 135 (2234+282, J2236+2828) has been proposed as a candidate compact symmetric object (CSO), based on its symmetric radio structure revealed by multi-frequency very long baseline interferometry (VLBI) imaging observations on milliarcsec angular scales. CSOs are known as young jetted active gal...
Based on the two epochs EVN archive data from OH line observations of IIZw 096, we confirm that the high-resolution OH emission in this source mainly comes from two spots (OH1 and OH2) of comp D1 of this merging system. We found no significant variations in the OH line emission.
We devise and exploit a data-driven, semi-empirical framework of galaxy formation and evolution, coupling it to recipes for planet formation from stellar and planetary science, to compute the cosmic planet formation rate, and the properties of the planets' preferred host stellar and galactic environments. We also ...
We present Herschel SPIRE Fourier Transform Spectrometer (FTS) observations of N159W, an active star-forming region in the Large Magellanic Cloud (LMC). In our observations, a number of far-infrared cooling lines including CO(4-3) to CO(12-11), [CI] 609 and 370 micron, and [NII] 205 micron are clearly detected.
Runaway stellar collisions in dense star clusters are invoked to explain the presence of very massive stars or blue stragglers in the center of those systems. This process has also been explored for the first star clusters in the Universe and shown to yield stars that may collapse at some points into an intermediate m...
Fitting parameterized models to images of galaxies has become the standard for measuring galaxy morphology. This forward modelling technique allows one to account for the PSF to effectively study semi-resolved galaxies.
We present the statistics of faint submillimeter/millimeter galaxies (SMGs) and serendipitous detections of a submillimeter/millimeter line emitter (SLE) with no multi-wavelength continuum counterpart revealed by the deep ALMA observations. We identify faint SMGs with flux densities of 0.1-1.0 mJy in the deep Band 6 a...
Here we review the efforts of a number of recent results that use old tracers to understand the build up of the Galaxy. Details that lead directly to using these old tracers to measure distances are discussed.
Recent optical surveys have found a rare population of low-$z$ ($z \sim 0.01 - 0.06$) extreme star-forming galaxies (xSFGs) that are the most metal-poor galaxies with strong emission lines, extremely high specific star-formation rate and low stellar mass. Using the Hubble Space Telescope Cosmic Origins Spectrograph, i...
We have conducted a spectral line survey in the 3 mm and 2 mm bands toward two positions in a spiral arm of M51 (NGC 5194) with the IRAM 30 m telescope. In this survey, we have identified 13 molecular species, including CN, CCH, N2H+, HNCO, and CH3OH.
Thanks to modern sky surveys, over twenty stellar streams and overdensity structures have been discovered in the halo of the Milky Way. In this paper, we present an analysis of spectroscopic observations of individual stars from one such structure, "A13", first identified as an overdensity using the M giant ca...
Fairall 51 is a polar-scattered Seyfert 1 galaxy, a type of active galaxies believed to represent a bridge between unobscured type-1 and obscured type-2 objects. Fairall 51 has shown complex and variable X-ray absorption but only little is known about its origin.
This paper documents the sixteenth data release (DR16) from the Sloan Digital Sky Surveys; the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the southern hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2...
The formation of massive stars is still not well understood. Accumulating a large amount of mass infalling within a single entity in spite of radiation pressure is possible if, among several other conditions, enough thermal energy is released.
Disk galaxies can exchange angular momentum and baryons with their host dark matter (DM) halos. These halos possess internal spin, `lambda', which is insignificant rotationally but does affect interactions between the baryonic and DM components.
We examine the HI gas kinematics of galaxy pairs in two clusters and a group using Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pilot survey observations. We compare the HI properties of galaxy pair candidates in the Hydra I and Norma clusters, and the NGC 4636 group, with those of non-paired control g...
It is speculated that the high star-formation efficiency observed in spiral-arm molecular clouds is linked to the prevalence of compressive (curl-free) turbulent modes, while the shear-driven solenoidal (divergence-free) modes appear to be the main cause of the low star-formation efficiency that characterises clouds in...
About 20 percent of all nearby early-type galaxies ($M_{\star} \gtrsim 6 \times 10^{9}$ M$_{\odot}$) outside the Virgo cluster are surrounded by a disc or ring of low-column-density neutral hydrogen (HI) gas with typical radii of tens of kpc, much larger than the stellar body. In order to understand the impact of thes...
The South Galactic Cap u-band Sky Survey (SCUSS) is a deep u-band imaging survey in the Southern Galactic Cap, using the 90Prime wide-field imager on the 2.3m Bok telescope at Kitt Peak. The survey observations started in 2010 and ended in 2013.
We have measured stellar photometry with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) in near ultraviolet (F275W, F336W), optical (F475W, F814W), and near infrared (F110W, F160W) bands for 117 million resolved stars in M31. As part of the Panchromatic Hubble Androme...
We present Atacama Large Millimeter/Submillimeter Array observations of the rest-frame far-infrared (FIR) dust continuum emission of six bright Lyman-break galaxies (LBGs) at $z \simeq 7$. One LBG is detected ($5.2\sigma$ at peak emission), while the others remain individually undetected at the $3\sigma$ level.
Interstellar polarimetric data of the six open clusters Hogg 15, NGC 6611, NGC 5606, NGC 6231, NGC 5749 and NGC 6250 have been used to estimate the membership probability for the stars within them. For proper-motion member stars, the membership probability estimated using the polarimetric data is in good agreement wit...
In this paper, we present a Ly$\alpha$ halo extended to $\sim200$ kpc identified by stacking $\sim 3300$ Ly$\alpha$ emitters at $z=2.2-2.3$. We carry out imaging observations and data reduction with Subaru/Hyper Suprime-Cam (HSC).
We report ALMA observations of polarized dust emission from the protostellar source Ser-emb 8 at a linear resolution of 140 au. Assuming models of dust-grain alignment hold, the observed polarization pattern gives a projected view of the magnetic field structure in this source.
Recent surveys uncovered new Young Massive Clusters (YMCs) that host dozens of Red Supergiants (RSGs) in the inner Milky Way. <br>These clusters are ideal for studying the most recent and violent star formation events in the inner Galaxy.
Certain lines in spectra of the Galactic microquasar SS 433, in particular the brilliant H alpha line, have been interpreted as emission from a circumbinary disk. In this interpretation the orbital speed of the glowing material is in excess of 200 km/s and the mass of the binary system in excess of 40 solar masses.
The gravitational wave detectors have unveiled a population of massive black holes that do not resemble those observed in the Milky Way and whose origin is debated. According to one possible explanation, these black holes may have formed from density fluctuations in the early Universe (primordial black holes), and the...
A method for investigating the sensitivity of the tip of the red giant branch (TRGB) I band magnitude $M_I$ to stellar input physics is presented. ~We compute a grid of $\sim$125,000 theoretical stellar models with varying mass, initial helium abundance, and initial metallicity, and train a machine learning emulator to...
We study galaxy interactions in the large scale environment around A2670, a massive ($M_{200}$ = $8.5 \pm 1.2~\times 10^{14} \mathrm{M_{\odot}}$) and interacting galaxy cluster at z = 0.0763. We first characterize the environment of the cluster out to 5$\times R_{200}$ and find a wealth of substructures, including the...
We find that significant incompleteness in stellar number counts results in a significant overestimate of the microlensing optical depth $\tau$ and event rate per star per year $\Gamma$ toward the Galactic bulge from the first two years of the MOA-II survey. We find that the completeness in Red Clump Giant (RCG) count...
Understanding our Galactic Center is easier with insights from nearby galactic nuclei. Both the star formation activity in nuclear gas disks, driven by bars and nuclear bars, and the fueling of low-luminosity AGN, followed by feedback of jets, driving molecular outflows, were certainly present in our Galactic Center, ...
To address questions about the physical nature and origin of spiral arms in galaxies, it is necessary to measure their dynamical properties, such as the angular speed, $\Omega_p$, or the corotation radius. Observations suggest that galaxies may contain several independent spiral patterns simultaneously.
We present a multiwavelength study of the gas distribution, kinematics and excitation of the OH megamaser galaxy IRAS 09320+6134 (UGC 5101) using Gemini Multi-Object Spectrograph Integral Field Unit, Hubble Space Telescope, and Very Large Array observations. The HST ACS F814W i-band and H$\alpha$ + [N II] $\lambda\lam...
We consider the morphology, stellar populations, structure and AGN activity of 10 post-starburst (K+A) galaxies with HST observations, full spectral coverage in the optical, spectral energy distributions from 0.2 to 160 $\mu$m, X-ray and radio data. Our results show that the PSG phenomenon is related to mergers and in...
We perform a super-resolution analysis of the Subaru Hyper Suprime-Cam (HSC) images to estimate the major merger fractions of z~4-7 dropout galaxies at the bright end of galaxy UV luminosity functions (LFs). Our super-resolution technique improves the spatial resolution of the ground-based HSC images, from ~1&#34; to ...
We used the data of 701 stars covering the colour index interval 0.32&lt;B-V&lt;=1.16, with metallicities -1.76&lt;=[Fe/H]&lt;=+0.40 dex, which were taken from PASTEL catalogue and estimated metallicity dependent guillotine factors which provide a more accurate metallicity calibration. We reduced the metallicities of ...
We present a spectroscopic study of the four extended star clusters (ESCs) in NGC 6822 based on the data obtained with Gemini Multi-Object Spectrograph (GMOS) on the Gemini-South 8.1m telescope. Their radial velocities derived from the spectra range from $-61.2 \pm 20.4$ km s$^{-1}$ (for C1) to $-115.34 \pm 57.9$ km s...
Dark matter-only simulations predict that dark matter halos have steep, cuspy inner density profiles, while observations of dwarf galaxies find a range of inner slopes that are often much shallower. There is debate whether this discrepancy can be explained by baryonic feedback or if it may require modified dark matter...
The aims are to investigate the clustering of the far-infrared sources from the Herschel infrared Galactic Plane Survey (Hi-GAL) in the Galactic longitude range of -71 to 67 deg. These clumps, and their spatial distribution, are an imprint of the original conditions within a molecular cloud.
This paper investigates C IV absorption in the circumgalactic medium (CGM) of L* galaxies and its relationship with galaxy star formation rates. We present new observations from the C IV in L* survey (CIViL*; PID$\#$17076) using the Hubble Space Telescope/Cosmic Origins Spectrograph.
We investigate the connection between ionized gas outflows and star formation activity using a large sample of type 1 and 2 AGNs with far-IR detections or star formation rate (SFR) estimates. The strength of ionized gas outflows, measured by the velocity dispersion and velocity shift of the \OIII\ emission line, clear...
We present James Webb Space Telescope (JWST) near-infrared (NIRCam) Br$\alpha$, H$_2$, [Fe II], and PAH imaging of the molecule-rich, high-excitation bipolar planetary nebula (PN) NGC 6537 (the Red Spider), complemented by new ALMA and Chandra observations and archival HST images. The resulting multiwavelength view of...
We use a composite gravitational galactic model consisting of a disk, a halo, a massive nucleus and a strong nuclear bar, in order to study the connections between global and local parameters in a realistic dynamical system. The local model is constructed from a two-dimensional perturbed harmonic oscillator and can be...
We have investigated the photo-stability of pristine and super-hydrogenated pyrene cations C$_{16}$H$_{10+m}^+, m = 0,6, \mathrm{\ or\ } 16$) by means of gas-phase action spectroscopy. Optical absorption spectra and photo-induced dissociation mass spectra are presented.
We investigate various galaxy population properties of the massive X-ray luminous galaxy cluster XDCP J0044.0-2033 at z=1.58, which constitutes the most extreme matter density peak at this redshift currently known. We analyze deep VLT/HAWK-I NIR data in the J- and Ks-bands, complemented by Subaru imaging in i and V, S...
Local starbursts have a higher efficiency of converting gas into stars, as compared to typical star-forming galaxies at a given stellar mass, possibly indicative of different modes of star formation. With the peak epoch of galaxy formation occurring at z &gt; 1, it remains to be established whether such an efficient m...
This paper summarises results from semi-analytical modelling of star formation in protocluster clumps of different metallicities. In this model, gravitationally bound cores form uniformly in the clump following a prescribed core formation efficiency per unit time.
We present two sets of grid-based hydrodynamical simulations of high-velocity clouds (HVCs) traveling through the diffuse, hot Galactic halo. These HI clouds have been suggested to provide fuel for ongoing star formation in the Galactic disk.
We present molecular line observations of the high-mass molecular clump IRAS 16562$-$3959 taken at 3 mm using the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.$\! \!
We report measurements of trigonometric parallax and proper motion for two 6.7 GHz methanol and two 22 GHz water masers located in the far portion of the Sagittarius spiral arm as part of the BeSSeL Survey. Distances for these sources are estimated from parallax measurements combined with 3-dimensional kinematic dista...
We report a detailed investigation of the bulk motions of the nearby Galactic stellar disk, based on three samples selected from the LSS-GAC DR2: a global sample containing 0.57 million FGK dwarfs out to $\sim$ 2 kpc, a local subset of the global sample consisting $\sim$ 5,400 stars within 150 pc, and an anti-center sa...
We present a dynamical study of the effect of the bar and spiral arms on the simulated orbits of open clusters in the Galaxy. Specifically, this work is devoted to the puzzling presence of high-altitude open clusters in the Galaxy.
Multi-epoch observations with ACS and WFC3 on HST provide a unique and comprehensive probe of stellar dynamics within 47 Tucanae. We confront analytic models of the globular cluster with the observed stellar proper motions that probe along the main sequence from just above 0.8 to 0.1M$_\odot$ as well as white dwarfs y...
We present the first galaxy-OVI absorption kinematic study for 20 absorption systems (EW&gt;0.1~Å) associated with isolated galaxies (0.15$&lt;z&lt;$0.55) that have accurate redshifts and rotation curves obtained using Keck/ESI. Our sample is split into two azimuthal angle bins: major axis ($\Phi&lt;25^{\circ}$) and m...
With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further frequency-dependent modulations in the strongly lensed GW signal within the LIG...
The search for the simplest amino acid, glycine (NH$_{2}$CH$_{2}$COOH), in the interstellar medium (ISM), has become a never-ending story for astrochemistry and astrophysics researchers because that molecule plays a possible connection between the Universe and the origin of life. In the last forty years, all searches ...