Hooshang Nayyeri
A5050088104- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- History and Developments in Astronomy
- Spectroscopy and Laser Applications
- Pulsars and Gravitational Waves Research
- CCD and CMOS Imaging Sensors
- Remote Sensing in Agriculture
- Cosmology and Gravitation Theories
- Robot Manipulation and Learning
- Dark Matter and Cosmic Phenomena
- Structural Analysis of Composite Materials
- Infrared Target Detection Methodologies
- Phase Equilibria and Thermodynamics
- Multimodal Machine Learning Applications
- Reinforcement Learning in Robotics
University of California, Irvine
2015-2023
University of California, Riverside
2011-2017
We present the results of our ultra-deep Keck/DEIMOS spectroscopy z-dropout galaxies in SDF and GOODS-N. For 3 out 11 objects, we detect an emission line at ~ 1um with a signal-to-noise ratio 10. The lines show asymmetric profiles high weighted skewness values, consistent being Lya, yielding redshifts z=7.213, 6.965, 6.844. Specifically, confirm z=7.213 object two independent DEIMOS runs different spectroscopic configurations. z=6.965 is known Lya emitter, IOK-1, for which improved spectrum...
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...
Abstract The study of galaxy evolution hinges on our ability to interpret multiwavelength observations in terms their physical properties. To do this, we rely spectral energy distribution (SED) models, which allow us infer parameters from spectrophotometric data. In recent years, thanks wide and deep multiwave band surveys, the volume high-quality data have significantly increased. Alongside increased data, algorithms performing SED fitting improved, including better modeling prescriptions,...
We present a 0.4-8$\mu$m multi-wavelength photometric catalog in the Extended Groth Strip (EGS) field. This is built on Hubble Space Telescope (HST) WFC3 and ACS data from Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), it incorporates existing HST All-wavelength strip International (AEGIS) 3D-HST program. The based detections F160W band reaching depth of F160W=26.62 AB (90% completeness, point-sources). It includes photometry for 41457 objects over an area $\approx...
We present a WFC3 F160W ($H$-band) selected catalog in the CANDELS/GOODS-N field containing photometry from ultraviolet (UV) to far-infrared (IR), photometric redshifts and stellar parameters derived analysis of multi-wavelength data. The contains 35,445 sources over 171 arcmin$^{2}$ CANDELS mosaic. 5$\sigma$ detection limits (within an aperture radius 0\farcs17) mosaic range between $H=27.8$, 28.2 28.7 wide, intermediate deep regions, that span approximately 50\%, 15\% 35\% total area....
We present a sample of 80 candidate strongly lensed galaxies with flux density above 100mJy at 500{\mu}m extracted from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS), over an area 600 square degrees. Available imaging and spectroscopic data allow us to confirm strong lensing in 20 cases reject it one case. For other 8 objects scenario is supported by presence two sources along same line sight distinct photometric redshifts. The remaining await more follow-up observations...
We present a multi-wavelength photometric catalog in the COSMOS field as part of observations by Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). The is based on Hubble Space Telescope Wide Field Camera 3 (HST/WFC3) and Advanced for Surveys (ACS) (centered at RA: $10^h00^m28^s$, Dec:$+02^{\circ}12^{\prime}21^{\prime\prime}$). final has 38671 sources with data forty two bands from UV to infrared ($\rm \sim 0.3-8\,\mu m$). This includes broad-band photometry HST, CFHT,...
We investigate the evolution of H β + [O iii] and ii] luminosity functions from z ∼ 0.8 to ∼5 in four redshift slices per emission line using data High-z Emission Line Survey (HiZELS). This is first time that have been studied at these redshifts a self-consistent analysis. also largest sample emitters (3475 3298 emitters, respectively) this range, with large comoving volumes ∼1 × 106 Mpc−3 two independent (COSMOS UDS), greatly reducing effects cosmic variance. The were selected by...
We report the discovery of a multiply imaged, gravitationally lensed type Ia supernova, iPTF16geu (SN 2016geu), at redshift z = 0.409. This phenomenon was identified because light from stellar explosion magnified more than 50 times by curvature space around matter in an intervening galaxy. used high-spatial-resolution observations to resolve four images approximately 0.3 arc seconds center foreground The probe physical scale ~1 kiloparsec, smaller is typical other studies extragalactic...
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...
Abstract We present a catalog of 10,718 objects in the COSMOS field, observed through multi-slit spectroscopy with Deep Imaging Multi-Object Spectrograph (DEIMOS) on Keck II telescope wavelength range ∼5500–9800 Å. The contains 6617 high-quality spectra (two or more spectral features), and 1798 single spectroscopic feature confirmed by photometric redshift. For 2024 typically faint objects, we could not obtain reliable redshifts. have been selected from variety input catalogs based...
We present Keck-I MOSFIRE near-infrared spectroscopy for a sample of 13 compact star-forming galaxies (SFGs) at redshift 2 ⩽ z 2.5 with star formation rates SFR ∼ 100 M☉ yr−1 and masses log(M/M☉) ∼10.8. Their high integrated gas velocity dispersions σint km s−1, as measured from emission lines Hα [O iii], the resultant M⋆–σint relation M⋆–Mdyn all match well to those quiescent 2, stellar absorption lines. Since log(M⋆/Mdyn) =−0.06 ± 0.2 dex, these SFGs appear be dynamically relaxed evolved,...
The rate of major galaxy–galaxy merging is theoretically predicted to steadily increase with redshift during the peak epoch massive galaxy development (1 ≤ z 3). We use close-pair statistics objectively study incidence galaxies (stellar M1 > 2 × 1010 M⊙) hosting companions M1/M2 4; i.e. <4:1) at six epochs spanning 0 < 3. select from a nearly complete, mass-limited (≥5 109 sample 23 696 in five Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey fields and Sloan Digital Sky...
We present results from the largest contiguous narrow-band survey in near-infrared. have used wide-field infrared camera/Canada–France–Hawaii Telescope and lowOH2 filter (1.187 ± 0.005 μm) to ≈10 deg2 of extragalactic sky SA22 field. A total ∼6000 candidate emission-line galaxies are found. use deep ugrizJK data obtain robust photometric redshifts. combine our with High-redshift(Z) Emission Line Survey (HiZELS), explore spectroscopic surveys (VVDS, VIPERS) own follow-up KMOS, FMOS MOSFIRE...
We investigate the properties of ∼7000 narrow-band selected galaxies with strong Hβ+[O iii] and [O ii] nebular emission lines from High-z Emission-Line Survey between z ∼ 0.8 5.0. Our sample covers a wide range in stellar mass (Mstellar 107.5–12.0 M⊙), rest-frame equivalent widths (EWrest∼10–105 Å), line luminosities (Lline 1040.5–43.2 erg s−1). measure iii]-selected functions out to 3.5 find that both M⋆ ϕ⋆ increases cosmic time. The ii]-selected show constant ≈ 1011.6 M⊙ strong, increasing...
We study the physical properties of a spectroscopic sample 28 star-forming galaxies in large filamentary structure COSMOS field at z ∼ 0.53, with data taken Keck/DEIMOS spectrograph, and compare them control 30 galaxies. spectroscopically confirm presence galaxy filament (∼8 Mpc), along which five confirmed X-ray groups exist. show that within uncertainties, ionization parameter, equivalent width (EW), EW versus specific star-formation rate (sSFR) relation, stellar mass line-of-sight...
Important but rare and subtle processes driving galaxy morphology star formation may be missed by traditional spiral, elliptical, irregular or Sérsic bulge/disc classifications. To overcome this limitation, we use a principal component analysis (PCA) of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, M20, multimode, intensity deviation) measured at rest-frame B band (corresponding to HST/WFC3 F125W 1.4 <z < 2) trace the natural distribution massive (>1010...
We use data taken as part of HST/WFC3 observations the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) to identify massive and evolved galaxies at 3<z<4.5. This is performed using strength Balmer break feature rest-frame 3648A, which a diagnostic age stellar population in galaxies. Using WFC3 H-band selected catalog for CANDELS GOODS-S field deep multi-waveband photometry from optical (HST) mid-infrared (Spitzer) wavelengths, we old post-starburst based on their...
We have modelled high resolution ALMA imaging of six strong gravitationally lensed galaxies detected by the Herschel Space Observatory. Our modelling recovers mass properties lensing and, determining magnification factors, intrinsic sub-millimetre sources. find that all ratios star formation rate to dust mass, consistent with or higher than mean ratio for redshift and low ultra-luminous infra-red galaxies. Source reconstruction reveals most exhibit disturbed morphologies. Both cleaned image...
ABSTRACT We present a list of candidate gravitationally lensed dusty star-forming galaxies (DSFGs) from the HerMES Large Mode Survey and Herschel Stripe 82 Survey. Together, these partially overlapping surveys cover 372 deg 2 on sky. After removing local spiral known radio-loud blazars, our DSFGs is composed 77 sources with 500 μ m flux densities ( S ) greater than 100 mJy. Such are starburst similar to first bright sub-millimeter (SMGs) discovered SCUBA. expect large fraction this be...
Using ALMA, we report high angular-resolution observations of the redshift z=3.63 galaxy, G09v1.97, one most luminous strongly lensed galaxies discovered by H-ATLAS survey. We present 0"2-0"4 resolution images rest-frame 188 and 419$\mu$m dust continuum CO(6-5), H2O(211-202) J=2 H2O+ line emission. also detection H$_2^{18}$O in this source. The molecular gas emission are resolved into a nearly complete ~1"5 diameter Einstein ring plus weaker image center, which is caused special dual...
Galaxy interactions and mergers are thought to play an important role in the evolution of galaxies. Studies nearby universe show a higher AGN fraction interacting merging galaxies than their isolated counterparts, indicating that such contributors black hole growth. To investigate this at redshifts, we have compiled largest known sample major spectroscopic galaxy pairs (2381 with $\Delta V <5000$ km s$^{-1}$) $0.5<z<3.0$ from observations COSMOS CANDELS surveys. We identify X-ray IR among...
Abstract We report the spectroscopic confirmation of a new protocluster in COSMOS field at z ∼ 2.2, Cluster 2.2 (CC2.2), originally identified as an overdensity narrowband selected H α emitting candidates. With only two masks Keck/MOSFIRE near-IR spectroscopy both (∼1.47–1.81 μ m) and K (∼1.92–2.40 bands (∼1.5 hr each), we confirm 35 unique members with least emission lines detected S/N > 3. Combined 12 extra from zCOSMOS-deep survey (47 total), estimate mean redshift line-of-sight...
Robots need to explore their surroundings adapt and tackle tasks in unknown environments. Prior work has proposed building scene graphs of the environment but typically assumes that is static, omitting regions require active interactions. This severely limits ability handle more complex household office environments: before setting up a table, robots must drawers cabinets locate all utensils condiments. In this work, we introduce novel task interactive exploration, wherein autonomously...