A5047566346- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Neutrino Physics Research
- Scientific Research and Discoveries
- Historical Astronomy and Related Studies
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Solar and Space Plasma Dynamics
- Science Education and Pedagogy
- Educational Strategies and Epistemologies
- Dark Matter and Cosmic Phenomena
- Various Chemistry Research Topics
- Astrophysics and Star Formation Studies
- Ancient Egypt and Archaeology
- Mitochondrial Function and Pathology
- History and Developments in Astronomy
- Nuclear Physics and Applications
American Museum of Natural History
2016-2025
University of Portsmouth
2021-2025
Lancaster University
2024
Centre National de la Recherche Scientifique
2024
Aix-Marseille Université
2024
Austin Peay State University
2024
University of Zurich
2024
American Public University System
2024
Stanford University
2024
Oak Ridge National Laboratory
2024
DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with wide-area galaxy quasar redshift survey. To trace underlying matter distribution, spectroscopic targets be selected in four classes from imaging data. We measure luminous red galaxies up to $z=1.0$. probe Universe out even higher redshift, target bright [O II] emission line $z=1.7$....
The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit multi-cycle treasury program to use the gravitational lensing properties of 25 galaxy clusters accurately constrain their mass distributions. survey, described in detail this paper, will definitively establish degree concentration dark matter cluster cores, key prediction CDM. CLASH sample larger and less biased than current samples space-based imaging studies similar depth, as we have minimized lensing-based...
In 1964, Refsdal hypothesized that a supernova whose light traversed multiple paths around strong gravitational lens could be used to measure the rate of cosmic expansion. We report discovery such system. Hubble Space Telescope imaging, we have found four images single forming an Einstein cross configuration redshift z=0.54 elliptical galaxy in MACS J1149.6+2223 cluster. The cluster's potential also creates z=1.49 spiral host galaxy, and future appearance elsewhere cluster field is expected....
We present an analysis of 15 Type Ia supernovae (SNe Ia) at redshift z > 1 (9 1.5 < 2.3) recently discovered in the CANDELS and CLASH Multi-Cycle Treasury programs using WFC3 on Hubble Space Telescope. combine these SNe with a new compilation 1050 Ia, jointly calibrated corrected for simulated survey biases to produce accurate distance measurements. unbiased constraints expansion rate six redshifts range 0.07 based only this combined SN sample. The added leverage our sample leads factor ~3...
DESI (Dark Energy Spectropic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations and the growth of structure through redshift-space distortions with wide-area galaxy quasar redshift survey. The instrument robotically-actuated, fiber-fed spectrograph capable taking up to 5,000 simultaneous spectra over wavelength range from 360 nm 980 nm. fibers feed ten three-arm spectrographs resolution $R= λ/Δλ$ between 2000 5500, depending on...
We present the first systematic investigation of spectral properties 17 Type Ic Supernovae (SNe Ic), 10 broad-lined SNe Ic-bl) without observed Gamma-Ray Bursts (GRBs) and 11 Ic-bl with GRBs (SN-GRBs) as a function time in order to probe their explosion conditions progenitors. analyze total 407 spectra, which were drawn from published spectra individual well densely time-sampled data Modjaz et al. (2014). In quantify diversity SN subtype, we construct average Ic, GRBs. find that 1994I is not...
The gravitationally lensed supernova Refsdal appeared in multiple images produced through gravitational lensing by a massive foreground galaxy cluster. After the 2014, lens models of cluster predicted that an additional image would appear 2015, which was subsequently observed. We use time delays between to perform blinded measurement expansion rate Universe, quantified Hubble constant (
Abstract We present cosmological constraints from the sample of Type Ia supernovae (SNe Ia) discovered and measured during full 5 yr Dark Energy Survey (DES) SN program. In contrast to most previous samples, in which SNe are classified based on their spectra, we classify DES using a machine learning algorithm applied light curves four photometric bands. Spectroscopic redshifts acquired dedicated follow-up survey host galaxies. After accounting for likelihood each being an Ia, find 1635...
We present cosmological constraints from the sample of Type Ia supernovae (SN Ia) discovered during full five years Dark Energy Survey (DES) Supernova Program. In contrast to most previous samples, in which SN are classified based on their spectra, we classify DES SNe using a machine learning algorithm applied light curves four photometric bands. Spectroscopic redshifts acquired dedicated follow-up survey host galaxies. After accounting for likelihood each being Ia, find 1635 redshift range...
Abstract Recent versions of the observed cosmic star formation history (SFH) have resolved an inconsistency with stellar mass density history. We show that revised SFH also scales up delay-time distribution (DTD) Type Ia supernovae (SNe Ia), as determined from volumetric SN rate history, aligning it other field-galaxy DTD measurements. The revised-SFH-based has a <?CDATA ${t}^{-1.1\pm 0.1}$?> form and Hubble-time-integrated production efficiency $N/{M}_{\star }=1.3\pm 0.1$?> SNe per...
We precisely constrain the inner mass profile of Abell 2261 (z=0.225) for first time and determine this cluster is not "over-concentrated" as found previously, implying a formation in agreement with ΛCDM expectations. These results are based on strong lensing analyses new 16-band HST imaging obtained part Cluster Lensing Supernova survey Hubble (CLASH). Combining revised weak Subaru wide field 5-band + KPNO photometry, we place tight constraints halo virial M_vir = 2.2\pm0.2\times10^15...
The Dark Energy Spectroscopic Instrument (DESI) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with wide-area galaxy quasar spectroscopic redshift survey. DESI instrument consists new wide-field (3.2 deg. linear field view) corrector plus multi-object spectrometer up to 5000 robotically positioned optical fibers be installed at prime focus on Mayall 4m telescope Kitt Peak,...
We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from Cluster Lensing And Supernova survey with Hubble (CLASH). Using Advanced Camera for Surveys Wide Field 3 on Space Telescope (HST), we have imaged 25 galaxy-cluster fields parallel of non-cluster galaxies. report a 27 SNe discovered in fields. Of these SNe, ∼13 are classified as Ia candidates, including four candidates at redshifts z > 1.2. measure volumetric to redshift 1.8 add first upper limit rate range < 2.4. The...
In Paper I of this series, we showed that the ratio between stripped-envelope (SE) supernova (SN) and Type II SN rates reveals a significant SE deficiency in galaxies with stellar masses $\lesssim 10^{10}~{\rm M}_\odot$. Here, test result by splitting volume-limited subsample Lick Observatory Supernova Search (LOSS) sample into low- high-mass comparing relative various types found them. The LOSS contains 180 SNe impostors is complete for Ia out to 80 Mpc core-collapse 60 Mpc. All these...
The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed total area of ~0.25 deg^2 with ~900 HST orbits spread across 5 fields over 3 years. Within these survey images we discovered 65 supernovae (SN) all types, out to z~2.5. We classify ~24 as Type Ia SN (SN Ia) based host-galaxy redshifts and photometry (supplemented by grism spectroscopy 6 SN). Here present measurement volumetric rate...
The Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) is a 101 orbit + parallel Cycle 25 Hubble Space Telescope Treasury program taking data from 2018-2020. BUFFALO will expand existing coverage of the (HFF) in WFC3/IR F105W, F125W, F160W ACS/WFC F606W F814W around each six HFF clusters flanking fields. This additional area has not been observed by HST but already covered deep multi-wavelength datasets, including Spitzer Chandra. As with original program, designed to take...
Abstract We present JWST near-infrared (NIR) and mid-infrared (MIR) spectroscopic observations of the nearby normal Type Ia supernova (SN) SN 2021aefx in nebular phase at +255 days past maximum light. Our Near Infrared Spectrograph (NIRSpec) Mid Instrument observations, combined with ground-based optical data from South African Large Telescope, constitute first complete optical+NIR+MIR spectrum covering 0.3–14 μ m. This unveils previously unobserved 2.5−5 m region, revealing strong iron...
We present the full Hubble diagram of photometrically-classified Type Ia supernovae (SNe Ia) from Dark Energy Survey supernova program (DES-SN). DES-SN discovered more than 20,000 SN candidates and obtained spectroscopic redshifts 7,000 host galaxies. Based on light-curve quality, we select 1635 photometrically-identified SNe with redshift 0.10$< z <$1.13, which is largest sample any single survey increases number known $z>0.5$ by a factor five. In companion paper, cosmological results...
Abstract We present the full Hubble diagram of photometrically classified Type Ia supernovae (SNe Ia) from Dark Energy Survey supernova program (DES-SN). DES-SN discovered more than 20,000 SN candidates and obtained spectroscopic redshifts 7000 host galaxies. Based on light-curve quality, we select 1635 identified SNe with redshift 0.10 < z 1.13, which is largest sample any single survey increases number known > 0.5 by a factor 5. In companion paper, cosmological results combined 194...
Abstract Extreme coronal line emitters (ECLEs) are a rare class of galaxy that exhibit strong, high-ionization iron emission lines in their spectra. In some cases, these transient and may be the result tidal disruption event (TDEs). To test this connection, we calculate rate variable ECLEs (vECLEs) at redshift ∼0.3. We search for Baryon Oscillation Spectroscopic Survey (BOSS) LOWZ sample discover two candidate ECLEs. Using follow-up spectra from Dark Energy Instrument Gemini Multi-Object...
Using a method to discover and classify supernovae (SNe) in galaxy spectra, we find 90 Type Ia SNe (SNe Ia) 10 II among the ~700,000 spectra Sloan Digital Sky Survey Data Release 7 that have VESPA-derived star-formation histories (SFHs). We use SN sample measure rates per unit stellar mass. confirm, at median redshift of sample, z = 0.1, inverse dependence on mass rate mass, previously reported by Li et al. (2011b) for local sample. further following Kistler (2011), this relation can be...
The Type Ia supernova (SN Ia) rate, when compared to the cosmic star formation history (SFH), can be used derive delay-time distribution (DTD; hypothetical SN rate versus time following a brief burst of formation) SNe Ia, which distinguish among progenitor models. We present results (SN) survey in Subaru Deep Field (SDF). Over period 3 years, we have observed SDF on four independent epochs with Suprime-Cam 8.2-m telescope, two nights exposure per epoch, R, i′and z′ bands. discovered 150 out...
We present the first year of Hubble Space Telescope imaging unique supernova (SN) 'Refsdal', a gravitationally lensed SN at z=1.488$\pm$0.001 with multiple images behind galaxy cluster MACS J1149.6+2223. The four observed Refsdal (images S1-S4) exhibited slow rise (over ~150 days) to reach broad peak brightness around 20 April, 2015. Using set light curve templates constructed from 1987A-like peculiar Type II SNe, we measure time delays for relative S1 4$\pm$4 (for S2), 2$\pm$5 (S3), and...