T. Matheson
A5016979058- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- Integrated Circuits and Semiconductor Failure Analysis
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Neutrino Physics Research
- Astrophysics and Star Formation Studies
- Calibration and Measurement Techniques
- SAS software applications and methods
- Solar and Space Plasma Dynamics
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Geological and Geophysical Studies
- Methane Hydrates and Related Phenomena
- Optical Systems and Laser Technology
- Particle accelerators and beam dynamics
- Scientific Computing and Data Management
- Atomic and Molecular Physics
NSF’s NOIRLab
2019-2024
Kitt Peak National Observatory
2012-2023
Community Science and Data Center
2023
University of Wisconsin–Madison
2020
Large Synoptic Survey Telescope Corporation
2020
Optica
2007-2019
The University of Tokyo
2005-2008
Tokyo University of Science
2005-2008
Max Planck Institute for Astrophysics
2005-2008
Trieste Astronomical Observatory
2005-2008
We report measurements of the mass density, ΩM, and cosmological-constant energy ΩΛ, universe based on analysis 42 type Ia supernovae discovered by Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 0.83, are fitted jointly with a set from Calán/Tololo Survey, below 0.1, to yield values cosmological parameters. All supernova peak magnitudes standardized using SN light-curve width-luminosity relation. measurement yields joint probability...
The High-z Supernova Search Team has discovered and observed 8 new supernovae in the redshift interval z=0.3-1.2. These independent observations, confirm result of Riess et al. (1998a) Perlmutter (1999) that supernova luminosity distances imply an accelerating universe. More importantly, they extend range consistently SN Ia to z~1, where signature cosmological effects opposite sign some plausible systematic effects. Consequently, these measurements not only provide another quantitative...
We have developed a technique to systematically discover and study high-redshift supernovae that can be used measure the cosmological parameters. report here results based on initial seven of more than 28 discovered date in supernova search Supernova Cosmology Project. find an observational dispersion peak magnitudes σMB=0.27; this narrows σMB, corr=0.19 after "correcting" using light-curve "width-luminosity" relation found for nearby (z ≤ 0.1) Type Ia from Calán/Tololo survey (Hamuy et...
We present early observations of the afterglow GRB 030329 and spectroscopic discovery its associated supernova SN 2003dh. obtained spectra each night from March 30.12 (0.6 days after burst) to April 8.13 (UT) (9.6 burst). The cover a wavelength range 350-850 nm. consist power-law continuum (Fν ∝ ν-0.9) with narrow emission lines originating H II regions in host galaxy, indicating low redshift z = 0.1687. However, our taken 2003 5 show broad peaks flux characteristic supernova. Correcting for...
We present UV, optical, and NIR photometry of the first electromagnetic counterpart to a gravitational wave source from Advanced LIGO/Virgo, binary neutron star merger GW170817. Our data set extends discovery optical at $0.47$ days $18.5$ post-merger, includes observations with Dark Energy Camera (DECam), Gemini-South/FLAMINGOS-2 (GS/F2), {\it Hubble Space Telescope} ({\it HST}). The spectral energy distribution (SED) inferred this $0.6$ is well described by blackbody model $T\approx 8300$...
We present constraints on the dark energy equation-of-state parameter, w=P/(rho c^2), using 60 Type Ia supernovae (SNe Ia) from ESSENCE supernova survey. derive a set of nature assuming flat Universe. By including (Omega_M, w) baryon acoustic oscillations, we obtain value for static parameter w=-1.05^{+0.13}_{-0.12} (stat; 1 sigma) +- 0.11 (sys) and Omega_M=0.274^{+0.033}_{-0.020} with best-fit chi^2/DoF 0.96. These results are consistent those reported by SuperNova Legacy Survey in similar...
The first cosmological results from the ESSENCE supernova survey (Wood-Vasey and coworkers) are extended to a wider range of models including dynamical dark energy nonstandard models. We fold in greater number external data sets such as recent Higher-z release high-redshift supernovae (Riess coworkers), well several complementary probes. Model comparison statistics Bayesian Akaike information criteria applied gauge worth These favor that give good fit with fewer parameters. Based on this...
Abstract We present the Dark Energy Camera (DECam) discovery of optical counterpart first binary neutron star merger detected through gravitational-wave emission, GW170817. Our observations commenced 10.5 hr post-merger, as soon localization region became accessible from Chile. imaged 70 deg 2 in i and z bands, covering 93% initial integrated probability, to a depth necessary identify likely counterparts (e.g., kilonova). At 11.4 post-merger we bright transient located nucleus NGC 4993 at...
We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11,500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains largest number homogeneously observed reduced nearby SNe Ia (z ≲ 0.08) published to date. It more than doubles sample, bringing SN cosmology point where systematic uncertainties dominate. Our natural system has a precision ≲0.02 mag in BVRIr'i' ≲0.04...
We present photometric and spectroscopic observations of SN 1991bg, a very peculiar Type Ia supernova located in the outskirts E1 galaxy NGC 4374 (M84) Virgo cluster. At maximum brightness 1991bg was 1.6 mag subluminous V 2.5 B, compared with normal SNe Ia. The colors were unusually red, but object not significantly reddened by dust. decline from certainly quite steep; we measure an initial linear fading 0.10 d^-1^ rather than typical value 0.06 for Ia, late- time 0.034 0.026 d^-1^....
We present photometric and spectroscopic observations of 23 high-redshift supernovae (SNe) spanning a range z = 0.34-1.03, nine which are unambiguously classified as Type Ia. These SNe were discovered during the IfA Deep Survey, began in 2001 September observed total 2.5 deg2 to depth approximately m ≈ 25-26 RIZ over 9-17 visits, typically every 1-3 weeks for nearly 5 months, with additional continuing until 2002 April. give brief description survey motivations, observational strategy,...
We present UBVRI photometry of 44 Type Ia supernovae (SNe Ia) observed from 1997 to 2001 as part a continuing monitoring campaign at the Fred Lawrence Whipple Observatory Harvard-Smithsonian Center for Astrophysics. The data set comprises 2190 observations and is largest homogeneously reduced sample SNe date, nearly doubling number well-observed, nearby with published multicolor CCD light curves. large U-band unique addition, important connections high redshift. decline rate SN curves...
We present a near-infrared spectral sequence of the electromagnetic counterpart to binary neutron star merger GW170817 detected by Advanced LIGO/Virgo. Our dataset comprises seven epochs J+H spectra taken with FLAMINGOS-2 on Gemini-South between 1.5 and 10.5 days after merger. In initial epoch, spectrum is dominated smooth blue continuum due high-velocity, lanthanide-poor kilonova component. Starting following night, all subsequent instead show features that are similar those predicted in...
In this first paper in a series we present 1298 low-redshift (z\leq0.2) optical spectra of 582 Type Ia supernovae (SNe Ia) observed from 1989 through 2008 as part the Berkeley SN Program (BSNIP). 584 199 SNe have well-calibrated light curves with measured distance moduli, and many been corrected for host-galaxy contamination. Most data were obtained using Kast double spectrograph mounted on Shane 3 m telescope at Lick Observatory typical wavelength range 3300-10,400 Ang., roughly twice wide...
We present 2603 spectra of 462 nearby Type Ia supernovae (SNe Ia), including 2065 previously unpublished spectra, obtained during 1993–2008 through the Center for Astrophysics Supernova Program. There are on average eight each 313 SNe with at least two spectra. Most were FAST spectrograph Fred Lawrence Whipple Observatory 1.5 m telescope and reduced in a consistent manner, making this data set well suited studies SN spectroscopic diversity. Using additional from literature, we study...
view Abstract Citations (347) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Peculiar Type IA SN 1991T: Detonation of a White Dwarf? Filippenko, Alexei V. ; Richmond, Michael W. Matheson, Thomas Shields, Joseph C. Burbidge, E. Margaret Cohen, Ross D. Dickinson, Mark Malkan, Matthew A. Nelson, Brant Pietz, Jochen Schlegel, David Schmeer, Patrick Spinrad, Hyron Steidel, Charles Tran, Hien Wren, William 1991T was peculiar object whose...
We present 30 optical spectra and 49 photometric epochs sampling the first 517 days after discovery of supernova (SN) 1999em derive its distance through expanding photosphere method (EPM). SN is shown to be a Type II‐plateau (II‐P) event, with plateau lasting until about 100 explosion. identify dominant ions responsible for most absorption features seen in portion spectrum during phase. Using weakest unblended estimate photospheric velocity, we find D = 8.2 ± 0.6 Mpc, an explosion date HJD...
We present results from the Hubble Higher z Supernova Search, first space-based open field survey for supernovae (SNe). In cooperation with Great Observatories Origins Deep Survey, we have used Space Telescope Advanced Camera Surveys to cover ~300 arcmin2 in area of Chandra Field South and North on five separate search epochs (separated by ~45 day intervals) a limiting magnitude F850LP ≈ 26. These deep observations allowed us discover 42 SNe redshift range 0.2 < 1.6. As these data span large...
We present photometric and spectroscopic observations of supernova (SN) 2002cx, which reveal it to be unique among all observed type Ia supernovae (SNe Ia). SN 2002cx exhibits a 1991T-like premaximum spectrum, 1991bg-like luminosity, expansion velocities roughly half those normal SNe Ia. Photometrically, has broad peak in the $R$ band plateau phase $I$ band, slow late-time decline. The $(B - V)$ color evolution is nearly normal, but $(V R)$ I)$ colors are very red. Early-time spectra evolve...
We present optical spectropolarimetry obtained at the Keck II 10 m telescope on 1998 March 7 UT along with total flux spectra spanning first 494 days after discovery (1998 2 UT) of peculiar Type IIn supernova (SN) 1998S. The SN is found to exhibit a high degree linear polarization, implying significant asphericity for its continuum-scattering environment. Prior removal interstellar polarization spectrum characterized by flat continuum (at p ≈ 2%) distinct changes in associated both broad...
The results of a worldwide coordinated observational campaign on the broad-lined Type Ic supernova (SN Ic) 2003jd are presented. In total, 74 photometric data points and 26 spectra were collected using 11 different telescopes. SN is one most luminous ever observed. A comparison with other supernovae (SNe confirms that represents an intermediate case between broad-line events (2002ap, 2006aj) highly energetic SNe (1997ef, 1998bw, 2003dh, 2003lw), ejected mass Mej= 3.0 ± 1 M⊙ kinetic energy...
view Abstract Citations (284) References (32) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Steps toward Determination of the Size and Structure Broad-Line Region in Active Galactic Nuclei. VIII. an Intensive HST, IUE, Ground-based Study NGC 5548 Korista, K. T. ; Alloin, D. Barr, P. Clavel, J. Cohen, R. Crenshaw, M. Evans, I. N. Horne, Koratkar, A. Kriss, G. Krolik, H. Malkan, Morris, S. L. Netzer, O'Brien, Peterson, B. Reichert, Rodriguez-Pascual,...
We describe the implementation and optimization of ESSENCE supernova survey, which we have undertaken to measure equation state parameter dark energy. present a method for optimizing survey exposure times cadence maximize our sensitivity energy w=P/rho c^2 given fixed amount telescope time. For on CTIO 4m telescope, measuring luminosity distances redshifts supernovae at modest (z~0.5 +- 0.2) is optimal determining w. data analysis pipeline based using reliable robust image subtraction find...
Core-collapse supernovae (CC-SNe) are the explosions that announce death of massive stars. Some CC-SNe linked to long-duration gamma-ray bursts (GRBs) and highly aspherical. One important question is what extent asphericity common all CC-SNe. Here we present late-time spectra for a number from stripped-envelope stars use them explore any generated in inner part exploding star, near site collapse. A range oxygen emission-line profiles observed, including high incidence double-peaked profiles,...
We present extensive optical and infrared photometry of the afterglow gamma-ray burst (GRB) 030329 its associated supernova (SN) 2003dh over first two months after detection (2003 March 30-May 29 UT). Optical spectroscopy from a variety telescopes is shown and, when combined with photometry, allows an unambiguous separation between SN contributions. The GRB initially power-law continuum but shows significant color variations during week that are unrelated to presence SN. early light curve...