A5073276467- Stellar, planetary, and galactic studies
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- CCD and CMOS Imaging Sensors
- Astro and Planetary Science
- History and Developments in Astronomy
- Cosmology and Gravitation Theories
- Planetary Science and Exploration
- Advanced Combustion Engine Technologies
- Dark Matter and Cosmic Phenomena
- Historical Astronomy and Related Studies
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
Princeton University
2018-2024
Rice University
2017-2019
We present the final results of Exploration Local VolumE Satellites (ELVES) Survey, a survey dwarf satellites nearly volume-limited sample Milky Way (MW)-like hosts in Volume. Hosts are selected simply via cut luminosity ($M_{K_s}<-22.1$ mag) and distance ($D<12$ Mpc). have cataloged 25 31 such hosts, with another five taken from literature. All surveyed out to at least 150 projected kpc ($\sim R_\mathrm{vir}/2$) majority 300 R_\mathrm{vir}$). detected using consistent semi-automated...
The structure of a dwarf galaxy is an important probe into the effects stellar feedback and environment. Using unprecedented sample 223 low-mass satellites from ongoing Exploration Local VolumE Satellites (ELVES) Survey, we explore structures in mass range $10^{5.5}<M_\star<10^{8.5}$M$_\odot$. We survey around $80\%$ massive, $M_K<-22.4$ mag, hosts Volume. Our complete to luminosities $M_V<-9$ mag surface brightness $\mu_{0,V}<26.5$ arcsec$^{-2}$ within at least $\sim200$ projected kpc....
Low-mass satellites around Milky Way (MW)-like galaxies are important probes of small scale structure and galaxy formation. However, confirmation satellite candidates with distance measurements remains a key barrier to fast progress in the Local Volume (LV). We measure surface brightness fluctuation (SBF) distances recently cataloged candidate dwarf 10 massive hosts within $D<12$ Mpc confirm association. The systems these complete mostly cleaned contaminants down $M_g{\sim}-9$ $-10$, area...
We present the properties of globular clusters (GCs) and nuclear star (NSCs) low-mass ($10^{5.5}<M_\star<10^{8.5}$ $M_\odot$) early-type satellites Milky Way-like small group hosts in Local Volume (LV) using deep, ground-based data from ongoing Exploration VolumE Satellites (ELVES) Survey. This sample 177 dwarfs significantly increases statistics for studying low-density environments, offering an important comparison to samples nearby galaxy clusters. The LV exhibit lower nucleation...
Abstract It has been shown that ultra-diffuse galaxies (UDGs) have higher specific frequencies of globular clusters, on average, than other dwarf with similar luminosities. The UDG NGC 5846-UDG1 is among the most extreme examples cluster–rich found so far. Here we present new Hubble Space Telescope observations and analysis this galaxy its cluster system. We find hosts 54 ± 9 three to four times more any previously known a luminosity reported in previous studies. With L V ,gal ≈ 6 × 10 7 ⊙ (...
We report on the discovery of a new Milky Way (MW) satellite in Bo\"otes based data from on-going Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). This satellite, named IV, is third ultra-faint dwarf that we have discovered HSC-SSP. identified statistically significant (32.3$\sigma$) overdensity stars having characteristics metal-poor, old stellar population. The distance to this system $D_{\odot}=209^{+20}_{-18}$ kpc with $V$-band absolute magnitude $M_V=-4.53^{+0.23}_{-0.21}$ mag....
Isolated dwarf galaxies usually exhibit robust star formation but satellite are often devoid of young stars, even in Milky Way-mass groups. Dwarf thus offer an important laboratory the environmental processes that cease formation. We explore balance quiescent and star-forming (quenched fractions) for a sample ~400 around 30 Local Volume hosts from Exploration VolumE Satellites (ELVES) Survey. present quenched fractions as function stellar mass, projected radius, host halo to conclude...
Abstract Quantifying the connection between galaxies and their host dark matter halos has been key for testing cosmological models on various scales. Below M ⋆ ∼ 10 9 ⊙ , such studies have primarily relied satellite galaxy population orbiting Milky Way (MW). Here we present new constraints subhalos using largest sample of in Local Volume ( D ≲ 12 Mpc) to date. We use 250 confirmed 71 candidate dwarf satellites around 27 MW-like hosts from Exploration VolumE Satellites (ELVES) Survey...
The radial spatial distribution of low-mass satellites around a Milky Way (MW)-like host is an important benchmark for simulations small-scale structure. sensitive to the disruption subhalos by central disk and can indicate whether observed in MW analogs artificial (i.e., numeric) or physical origin. We consider sample 12 well-surveyed satellite systems MW-like hosts Local Volume that are complete $M_V<-9$ within 150 projected kpc. investigate compare with $\Lambda$CDM cosmological...
We explore the use of ground-based surface brightness fluctuation (SBF) measurements to constrain distances nearby dwarf galaxies. Using archival CFHT Megacam imaging data for a sample 27 dwarfs, we demonstrate that reliable SBF and accurate 15\% are possible even very low (LSB, $\mu_{i0}>24$ mag/arcsec$^2$) galaxies with modest, $\sim$hour-long exposures CFHT. Combining our recent 7 dwarfs measured HST from literature, provide most robust empirical calibration to-date blue colors expected...
Abstract We present an in-depth study of surface brightness fluctuations (SBFs) in low-luminosity stellar systems. Using the MIST models, we compute theoretical predictions for absolute SBF magnitudes LSST, HST ACS/WFC, and proposed Roman Space Telescope filter compare our calculations to observed SBF–color relations systems that span a wide range age metallicity. Consistent with previous studies, find single-age population models show excellent agreement observations low-mass galaxies 0.5 ≲...
Abstract The relationship between galaxies and the state/chemical enrichment of warm–hot intergalactic medium (WHIM) expected to dominate baryon budget at low- z provides sensitive constraints on structure formation galaxy evolution models. We present a deep redshift survey in field 1ES1553+113, blazar with unique combination ultraviolet (UV)+X-ray spectra for surveys circumgalactic/intergalactic (CGM/IGM). Nicastro et al. reported detection two O vii WHIM absorbers = 0.4339 0.3551 its...
We present the results of an extensive search for dwarf satellite galaxies around 10 primary host in Local Volume (D$<$12 Mpc) using archival CFHT/MegaCam imaging data. The hosts span a wide range properties, with stellar masses ranging from that LMC to ${\sim}3$ times Milky Way (MW). surveyed are: NGC 1023, 1156, 2903, 4258, 4565, 4631, 5023, M51, M64, and M104. detect candidates consistent semi-automated detection algorithm is optimized low surface brightness objects. Depending on host,...
Abstract We use surface brightness fluctuation (SBF) measurements to constrain the distance low (LSB) dwarfs in vicinity of M101. Recent work has discovered many LSB candidate satellite companions However, without accurate distances, it is problematic identify these as physical satellites CFHT Legacy Survey data measure SBF signal for 43 dwarfs. The are deep enough that we 33 be unassociated background galaxies by their lack SBF. high S/N signals two dwarfs, which consistent with being at...
Abstract We analyze the photometric data in Wide layer of Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) over ∼1200 deg2 to uncover new halo substructures beyond distance, D⊙ ∼ 30 kpc, from Sun. For this purpose, we develop an isochrone filter for old, metal-poor stellar system extract faint main-sequence stars at a range distances. With method, detect not only previously discovered such as Orphan Stream, but also overdensity toward Boötes about 60 kpc and stream-like feature Pisces...
We conduct a comprehensive and statistical study of the luminosity functions (LFs) for satellite galaxies, by counting photometric galaxies from HSC, DECaLS SDSS around isolated central (ICGs) paired SDSS/DR7 spectroscopic sample. Results different surveys show very good agreement. The LFs can be measured down to $M_V\sim-10$, primary as small $8.5<\log_{10}M_\ast/M_\odot<9.2$ $9.2<\log_{10}M_\ast/M_\odot<9.9$, implying there are on average 3--8 satellites with $M_V<-10$ LMC-mass ICGs....
Wavelength-dependent PSFs and their impact on weak lensing measurements S G Carlsten, Carlsten Department of Astrophysical Sciences, 4 Ivy Lane, Princeton University, Princeton, NJ 08544, USA E-mail: scottgc@princeton.edu Search for other works by this author on: Oxford Academic Google Scholar ADS Michael A Strauss, Strauss Robert H Lupton, Lupton Joshua E Meyers, Meyers USAKavli Institute Particle Astrophysics Cosmology, Physics, Stanford Stanford, CA 94305, Satoshi Miyazaki National...
We explore non-adiabatic particle production in a de Sitter universe for scalar spectator field, by allowing the effective mass m2(t) of this field and cosmic time interval between events to vary stochastically. Two main scenarios are considered depending on (non-stochastic) M field: conformal case with M2=2H2, massless field. make use transfer matrix formalism parametrize evolution system terms "occupation number", two phases associated matrix; these used construct Assuming short-time...
Abstract We are conducting a survey using twilight time on the Dark Energy Camera with Blanco 4 m telescope in Chile to look for objects interior Earth’s and Venus’ orbits. To date we have discovered two rare Atira/Apohele asteroids, 2021 LJ4 PH27, which orbits completely orbit. also one new Apollo-type Near Earth Object (NEO) that crosses orbit, 2022 AP7. Two of discoveries diameters ≳1 km. AP7 is likely largest Potentially Hazardous Asteroid (PHA) about eight years. covered 624 square...
Abstract It is well known that almost all isolated dwarf galaxies are actively forming stars. We report the discovery of dw1322m2053 (nicknamed Hedgehog), an quiescent galaxy at a distance 2.40 ± 0.15 Mpc with stellar mass M ⋆ ≈ 10 5.8 ⊙ . The measured using surface brightness fluctuations both Legacy Surveys and deep Magellan/IMACS imaging data. Hedgehog 1.7 from nearest group, Centaurus A, has no neighboring within 1 Mpc, making it one most this mass. red optical color early-type...
We present a study of the inner (out to $\sim$1 R$_{\mathrm{eff}}$) stellar populations 9 shell galaxies. derive population parameters from long slit spectra by both analyzing Lick indices galaxies and fitting Single Stellar Population model full galaxy spectra. The results two methods agree reasonably well. Many in our sample appear have lower central $\mathrm{Mg}_{2}$ index values than non-shell same velocity dispersion, which is likely due past interaction event. Our shows relation...
Abstract We examine new and pre-existing wide-field, continuum-corrected, narrowband images in H 2 1-0 S(1) Br γ of three regions massive star formation: IC 1396, Cygnus OB2, Carina. These contain a variety globules, pillars, sheets, so we can quantify how the spatial profiles emission lines behave photodissociation (PDRs) that differ their radiation fields geometries. have measured 450 along interfaces between ii PDRs. traces photoevaporative flows from PDRs, this declines more rapidly with...
It is well known that almost all isolated dwarf galaxies are actively forming stars. We report the discovery of Hedgehog, an quiescent galaxy at a distance $2.41\pm0.14$ Mpc with stellar mass $M_\star \approx 10^{5.8}\, M_\odot$. The measured using surface brightness fluctuations both Legacy Surveys and deep Magellan/IMACS imaging data. Hedgehog 1.7 from nearest group, Centaurus A, has no neighboring within 1 Mpc, making it one most dwarfs this mass. red optical color, early-type morphology,...