Timothy W. Ross
A5013074515- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Adaptive optics and wavefront sensing
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Toxoplasma gondii Research Studies
- Mitochondrial Function and Pathology
University of California, Berkeley
2017-2024
Lumentum (United States)
2024
We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on 3-m Shane telescope at Lick Observatory from April 2016 to May 2017. Targeting active galactic nuclei (AGN) with luminosities {\lambda}L{\lambda} (5100 {\AA}) = 10^44 erg/s and predicted H{\beta} lags 20-30 days or black hole masses 10^7-10^8.5 Msun, our campaign probes luminosity-dependent trends in broad-line region (BLR) structure dynamics as well improve calibrations for...
We present BVRI and unfiltered light curves of 93 Type Ia supernovae (SNe Ia) from the Lick Observatory Supernova Search (LOSS) follow-up program conducted between 2005 2018. Our sample consists 78 spectroscopically normal SNe Ia, with remainder divided distinct subclasses (three SN 1991bg-like, three 1991T-like, four Iax, two peculiar, super-Chandrasekhar events), has a median redshift 0.0192. The in our have coverage 16 photometric epochs at cadence 5.4 days, first observed epoch is ~4.6...
In this work, BV RI light curves of 55 Type II supernovae (SNe II) from the Lick Observatory Supernova Search program obtained with Katzman Automatic Imaging Telescope and 1 m Nickel telescope 2006 to 2018 are presented. Additionally, more than 150 spectra gathered 3 Shane published. We conduct an analyse peak absolute magnitudes, decline rates, time durations different phases colour curves. Typically, our sampled a median cadence 5.5 days for total 5093 photometric points. average V-band...
A galaxy cluster acts as a cosmic telescope over background galaxies but also microscope of the lens imperfections. The diverging magnification lensing caustics enhances microlensing effect substructure present within mass. Fine-scale structure can be accessed moving source brightens and disappears when crossing these caustics. recent recognition distant lensed star near Einstein radius MACSJ1149.5+2223 (Kelly et al. 2017) allows rare opportunity to reach subsolar mass through super-critical...
We have modeled the velocity-resolved reverberation response of H\b{eta} broad emission line in nine Seyfert 1 galaxies from Lick Active Galactic Nucleus (AGN) Monitioring Project 2016 sample, drawing inferences on geometry and structure low-ionization broad-line region (BLR) mass central supermassive black hole. Overall, we find that BLR is generally a thick disk viewed at low to moderate inclination angles. combine our sample with prior studies investigate line-profile shape dependence,...
We present observations of the extremely luminous but ambiguous nuclear transient (ANT) ASASSN-17jz, spanning roughly 1200 days object's evolution. ASASSN-17jz was discovered by All-Sky Automated Survey for Supernovae (ASAS-SN) in galaxy SDSS J171955.84+414049.4 on UT 2017 July 27 at a redshift $z=0.1641$. The peaked an absolute $B$-band magnitude $M_{B,{\rm peak}}=-22.81$, corresponding to bolometric luminosity $L_{\rm bol,peak}=8.3\times10^{44}$~erg~s$^{-1}$, and exhibited late-time...
Abstract We present extensive optical photometric and spectroscopic observations, from 4 to 482 days after explosion, of the Type II-plateau (II-P) supernova (SN) 2017eaw in NGC 6946. SN is a normal II-P intermediate properties between, for example, 1999em 2012aw more luminous 2004et, also have determined that extinction primarily due Galactic foreground site metallicity likely subsolar. independently confirmed tip-of-the-red-giant-branch (TRGB) distance 6946 7.73 ± 0.78 Mpc. The distances...
Abstract Over recent decades, robotic (or highly automated) searches for supernovae (SNe) have discovered several thousand events, many of them in quite nearby galaxies (distances < 30 Mpc). Most these SNe, including some the best-studied events to date, were found before maximum brightness and associated with extensive follow-up photometry spectroscopy. Some discoveries are so-called “SN impostors,” thought be superoutbursts luminous blue variable stars, although possibly a new, weak...
We present BVRI and unfiltered Clear light curves of 70 stripped-envelope supernovae (SESNe), observed between 2003 2020, from the Lick Observatory Supernova Search (LOSS) follow-up program. Our SESN sample consists 19 spectroscopically normal SNe~Ib, two peculiar SNe Ib, six SN Ibn, 14 Ic, one ten Ic-BL, 15 IIb, ambiguous IIb/Ib/c, superluminous SNe. photometry has (on a per-SN basis) mean coverage 81 photometric points (median 58 points) cadence 3.6d 1.2d). From our full sample, subset 38...
We present photometry, spectroscopy, and host-galaxy integral-field spectroscopy of the Type II supernova (SN) 2016esw in CGCG~229-009 from first day after explosion up to 120 days. Its light-curve shape is similar that a typical SN II; however, near high-luminosity end distribution, with peak $M^{\rm max}_{V}=-18.36$ mag. The $V$-band light curve exhibits long recombination phase for (similar long-lived plateau 2004et). Considering well-known relation between luminosity decline rate, should...
Abstract We present extensive optical photometric and spectroscopic observations of the high-velocity (HV) Type Ia supernova (SN Ia) 2017fgc, covering phase from ∼12 days before to ∼389 after maximum brightness. SN 2017fgc is similar normal SNe Ia, with an absolute peak magnitude <?CDATA ${M}_{\max }^{B}\approx $?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mi>max</mml:mi> <mml:mi>B</mml:mi>...
Photometric and spectroscopic analyses of the intermediate-luminosity Type Ib supernova (SN) 2015ap heavily reddened SN~2016bau are discussed. properties two SNe, such as colour evolution, bolometric luminosity, photospheric radius, temperature, velocity also constrained. The ejecta mass, synthesised nickel kinetic energy calculated from their light-curve analysis. We model compare spectra SN~2015ap at various stages evolution. P~Cygni profiles lines present in used to determine evolution...
Over recent decades, robotic (or highly automated) searches for supernovae (SNe) have discovered several thousand events, many of them in quite nearby galaxies (distances < 30 Mpc). Most these SNe, including some the best-studied events to date, were found before maximum brightness and associated with extensive follow-up photometry spectroscopy. Some discoveries are so-called SN impostors, thought be superoutbursts luminous blue variable stars, although possibly a new, weak class...
Abstract We present extensive, well-sampled optical and ultraviolet photometry spectra of the Type Ia supernova (SN Ia) 2017hpa. The light curves indicate that SN 2017hpa is a normal with an absolute peak magnitude <?CDATA ${M}_{\max }^{B}\approx $?> −19.12 ± 0.11 mag postpeak decline rate Δ m 15 ( B ) = 1.02 0.07 mag. According to quasi-bolometric curve, we derive luminosity 1.25 × 10 43 erg s −1 56 Ni mass 0.63 0.02 M ⊙ . spectral evolution similar supernovae (SNe Ia), while it exhibits...