E. Y. Hsiao

Florida State University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

M. Stritzinger

Aarhus University

M. M. Phillips

Las Campanas Observatory

N. Morrell

Las Campanas Observatory

D. A. Howell

Las Cumbres Observatory Global Telescope Network

L. Galbany

Institut d'Estudis Espacials de Catalunya

J. P. Anderson

Dartmouth College

C. Contreras

Universidad Mayor

M. Sullivan

University of Southampton

P. A. Mazzali

Max Planck Institute for Astrophysics

P. Nugent

Lawrence Berkeley National Laboratory

Cooperative Institutions

Centre National de la Recherche Scientifique

University of California, Berkeley

California Institute of Technology

Cerro Tololo Inter-American Observatory

Stockholm University

Lawrence Berkeley National Laboratory

Astronomical Observatory

Center for Astrophysics Harvard & Smithsonian

AlbaNova

South African Radio Astronomy Observatory

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

The delay of shock breakout due to circumstellar material evident in most type II supernovae

Nature Astronomy (2018)

F. Förster Takashi J. Moriya J. C. Maureira J. P. Anderson С. И. Блинников

Circumstellar envelope

10.1038/s41550-018-0563-4

Cite

Citations (116)

Photometric and spectroscopic evolution of the interacting transient AT 2016jbu(Gaia16cfr)

Monthly Notices of the Royal Astronomical Society (2022)

S. Brennan M. Fraser J. Johansson A. Pastorello R. Kotak

We present the results from a high cadence, multi-wavelength observation campaign of AT 2016jbu (aka Gaia16cfr), an interacting transient. This dataset complements the current literature by adding higher cadence as well as extended coverage of the lightcurve evolution and late-time spectroscopic evolution. Photometric coverage reveals that AT 2016jbu underwent significant photometric variability followed by two luminous events, the latter of which reached an absolute magnitude of M$_V\sim$-18.5 mag. This is similar to the transient SN 2009ip whose nature is still debated. Spectra are dominated by narrow emission lines and show a blue continuum during the peak of the second event. AT 2016jbu shows signatures of a complex, non-homogeneous circumstellar material (CSM). We see slowly evolving asymmetric hydrogen line profiles, with velocities of 500km$s^{-1}$ seen in narrow emission features from a slow moving CSM, and up to 10,000km$s^{-1}$ seen in broad absorption from some high velocity material. Late-time spectra ($\sim$+1 year) show a lack of forbidden emission lines expected from a core-collapse supernova and are dominated by strong emission from H, He i and Ca ii. Strong asymmetric emission features, a bumpy lightcurve, and continually evolving spectra suggest an inhibit nebular phase. We compare the evolution of H$\alpha$ among SN 2009ip-like transients and find possible evidence for orientation angle effects. The light-curve evolution of AT 2016jbu suggests similar, but not identical, circumstellar environments to other SN 2009ip-like transients.

AKA

10.1093/mnras/stac1243

Cite

Citations (18)

WiFeS+FIRE classification of ASASSN-14lw as a young SN Ia

The astronomer's telegram (2014)

M. Childress T. Diamond R. Scalzo C. Contreras B. Tucker

Source

Cite

Citations (0)

Multi-epoch high-spectral-resolution observations of neutral sodium in 14 Type Ia supernovae★

Monthly Notices of the Royal Astronomical Society (2014)

A. Sternberg A. Gal‐Yam Joshua D. Simon F. Patat W. Hillebrandt

One of the main questions concerning Type Ia supernovae is the nature of the binary companion of the exploding white dwarf. A major discriminant between different suggested models is the presence and physical properties of circumstellar material at the time of explosion. If present, this material will be ionized by the ultraviolet radiation of the explosion and later recombine. This ionization–recombination should manifest itself as time-variable absorption features that can be detected via multi-epoch high-spectral-resolution observations. Previous studies have shown that the strongest effect is seen in the neutral sodium D lines. We report on observations of neutral sodium absorption features observed in multi-epoch high-resolution spectra of 14 Type Ia supernova events. This is the first multi-epoch high-resolution study to include multiple SNe. No variability in line strength that can be associated with circumstellar material is detected in the events presented in this paper. If we include previously published events, we find that ∼18 per cent of the events in the extended sample exhibit time-variable sodium features associated with circumstellar material. We explore the implication of this study on our understanding of the progenitor systems of Type Ia supernovae via the current Type Ia supernova multi-epoch high-spectral-resolution sample.

Epoch (astronomy)

Line (geometry)

10.1093/mnras/stu1202

Cite

Citations (44)

Optical Spectroscopy of the transient pulsar and Be/X-ray binary V0332+53

The astronomer's telegram (2008)

E. Y. Hsiao M. L. Graham C. J. Pritchet A. H. Parker Sarah Sadavoy

Transient (computer programming)

X-ray binary

Source

Cite

Citations (0)

Spectral models for early time SN 2011fe observations

Monthly Notices of the Royal Astronomical Society (2015)

E. Baron P. Hoêflich Brian Friesen M. Sullivan E. Y. Hsiao

We use observed UV through near IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal SNe Ia and to examine its individual peculiarities. As a benchmark, we use a delayed-detonation model with a progenitor metallicity of Z_solar/20. We study the sensitivity of features to variations in progenitor metallicity, the outer density profile, and the distribution of radioactive nickel. The effect of metallicity variations in the progenitor have a relatively small effect on the synthetic spectra. We also find that the abundance stratification of SN 2011fe resembles closely that of a delayed detonation model with a transition density that has been fit to other Branch-normal Type Ia supernovae. At early times, the model photosphere is formed in material with velocities that are too high, indicating that the photosphere recedes too slowly or that SN 2011fe has a lower specific energy in the outer ~0.1 M_sun than does the model. We discuss several explanations for the discrepancies. Finally, we examine variations in both the spectral energy distribution and in the colors due to variations in the progenitor metallicity, which suggests that colors are only weak indicators for the progenitor metallicity, in the particular explosion model that we have studied. We do find that the flux in the U band is significantly higher at maximum light in the solar metallicity model than in the lower metallicity model and the lower metallicity model much better matches the observed spectrum.

Photosphere

10.1093/mnras/stv1951

Cite

Citations (11)

Lensed Type Ia supernovae as probes of cluster mass models

Monthly Notices of the Royal Astronomical Society (2014)

J. Nordin D. Rubin Johan Richard E. S. Rykoff G. Aldering

Using three magnified Type Ia supernovae (SNe Ia) detected behind CLASH (Cluster Lensing and Supernovae with Hubble) clusters, we perform a first pilot study to see whether standardizable candles can be used to calibrate cluster mass maps created from strong lensing observations. Such calibrations will be crucial when next-generation Hubble Space Telescope cluster surveys (e.g. Frontier) provide magnification maps that will, in turn, form the basis for the exploration of the high-redshift Universe. We classify SNe using combined photometric and spectroscopic observations, finding two of the three to be clearly of Type Ia and the third probable. The SNe exhibit significant amplification, up to a factor of 1.7 at ∼5σ significance (SN-L2). We conducted this as a blind study to avoid fine-tuning of parameters, finding a mean amplification difference between SNe and the cluster lensing models of 0.09 ± 0.09stat ± 0.05sys舁mag. This impressive agreement suggests no tension between cluster mass models and high-redshift-standardized SNe Ia. However, the measured statistical dispersion of σμ = 0.21舁mag appeared large compared to the dispersion expected based on statistical uncertainties (0.14). Further work with the SN and cluster lensing models, post-unblinding, reduced the measured dispersion to σμ = 0.12. An explicit choice should thus be made as to whether SNe are used unblinded to improve the model, or blinded to test the model. As the lensed SN samples grow larger, this technique will allow improved constraints on assumptions regarding e.g. the structure of the dark matter halo.

Cosmic distance ladder

10.1093/mnras/stu376

Cite

Citations (39)

FIRE spectroscopic classification of OGLE-2014-SN-014

The astronomer's telegram (2014)

G. H. Marion S. Holmbo Ł. Wyrzykowski A. Udalski S. Kozłowski

Source

Cite

Citations (0)

Gaia16apd – a link between fast and slowly declining type I superluminous supernovae

Monthly Notices of the Royal Astronomical Society (2017)

T. Kangas N. Blagorodnova S. Mattila P. Lundqvist M. Fraser

We present ultraviolet, optical and infrared photometry and optical spectroscopy of the type Ic superluminous supernova (SLSN) Gaia16apd (= SN 2016eay), covering its evolution from 26 d before the $g$-band peak to 234.1 d after the peak. Gaia16apd was followed as a part of the NOT Unbiased Transient Survey (NUTS). It is one of the closest SLSNe known ($z = 0.102\pm0.001$), with detailed optical and ultraviolet (UV) observations covering the peak. Gaia16apd is a spectroscopically typical type Ic SLSN, exhibiting the characteristic blue early spectra with O II absorption, and reaches a peak $M_{g} = -21.8 \pm 0.1$ mag. However, photometrically it exhibits an evolution intermediate between the fast- and slowly-declining type Ic SLSNe, with an early evolution closer to the fast-declining events. Together with LSQ12dlf, another SLSN with similar properties, it demonstrates a possible continuum between fast- and slowly-declining events. It is unusually UV-bright even for a SLSN, reaching a non-$K$-corrected $M_{uvm2} \simeq -23.3$ mag, the only other type Ic SLSN with similar UV brightness being SN 2010gx. Assuming that Gaia16apd was powered by magnetar spin-down, we derive a period of $P = 1.9\pm0.2$ ms and a magnetic field of $B = 1.9\pm0.2 \times 10^{14}$ G for the magnetar. The estimated ejecta mass is between 8 and 16 $\mathrm{M}_{\odot}$ and the kinetic energy between 1.3 and $2.5 \times 10^{52}$ erg, depending on opacity and assuming that the entire ejecta is swept up into a thin shell. Despite the early photometric differences, the spectra at late times are similar to slowly-declining type Ic SLSNe, implying that the two subclasses originate from similar progenitors.

Magnetar

10.1093/mnras/stx833

Cite

Citations (46)

Atmospheric extinction properties above Mauna Kea from the Nearby SuperNova Factory spectro-photometric data set

Astronomy and Astrophysics (2012)

C. Buton Y. Copin G. Aldering P. Antilogus C. Aragon

We present a new atmospheric extinction curve for Mauna Kea spanning 3200--9700 \AA. It is the most comprehensive to date, being based on some 4285 standard star spectra obtained on 478 nights spread over a period of 7 years obtained by the Nearby SuperNova Factory using the SuperNova Integral Field Spectrograph. This mean curve and its dispersion can be used as an aid in calibrating spectroscopic or imaging data from Mauna Kea, and in estimating the calibration uncertainty associated with the use of a mean extinction curve. Our method for decomposing the extinction curve into physical components, and the ability to determine the chromatic portion of the extinction even on cloudy nights, is described and verified over the wide range of conditions sampled by our large dataset. We demonstrate good agreement with atmospheric science data obtain at nearby Mauna Loa Observatory, and with previously published measurements of the extinction above Mauna Kea.

Extinction (optical mineralogy)

10.1051/0004-6361/201219834

Cite

Citations (99)