A5077055351- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Neutrino Physics Research
- Calibration and Measurement Techniques
- Solar and Space Plasma Dynamics
- Spectroscopy and Laser Applications
- Nuclear Physics and Applications
- Scientific Research and Discoveries
- Geophysics and Gravity Measurements
- History and Developments in Astronomy
- Geological and Geophysical Studies
- Cosmology and Gravitation Theories
- Spacecraft and Cryogenic Technologies
- Atomic and Molecular Physics
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
Las Campanas Observatory
2015-2024
Middlebury College
2024
Carnegie Institution for Science
2010-2022
Carnegie Observatories
2009-2022
University of Warsaw
2022
Florida State University
2019
Max Planck Institute for Astrophysics
2018
California Institute of Technology
2015
San Diego State University
2012
University of Copenhagen
2012
We present spectral and photometric observations of 10 Type Ia supernovae (SNe Ia) in the redshift range 0.16 ≤ z 0.62. The luminosity distances these objects are determined by methods that employ relations between SN light curve shape. Combined with previous data from our High-z Supernova Search Team recent results Riess et al., this expanded set 16 high-redshift a 34 nearby used to place constraints on following cosmological parameters: Hubble constant (H0), mass density (ΩM), (i.e.,...
An investigation is made of the merits various emission-line intensity ratios for classifying spectra extragalactic objects. It shown empirically that several combinations easily-measured lines can be used to separate objects into one four categories according principal excitation mechanism: normal H II regions, planetary nebulae, photoionized by a power-law continuum, and excited shock-wave heating. A two-dimensional quantitative classification scheme suggested.
view Abstract Citations (1716) References (30) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Absolute Magnitudes of Type IA Supernovae Phillips, M. magnitudes in the B, V, and I bands are derived for nine well-observed Ia supernovae using host galaxy distances estimated via surface brightness fluctuations or Tully-Fisher methods. These data indicate that there is a significant intrinsic dispersion absolute at maximum light supernovae, amounting to +/-...
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...
After the All-Sky Automated Survey for SuperNovae (ASAS-SN) discovered a significant brightening of inner region NGC 2617, we began ~70 day photometric and spectroscopic monitoring campaign from X-ray through near-infrared (NIR) wavelengths. We report that 2617 went dramatic outburst, during which its flux increased by over an order magnitude followed increase optical/ultraviolet (UV) continuum almost magnitude. classified as Seyfert 1.8 galaxy in 2003, is now 1 due to appearance broad...
We present a new compilation of Type Ia supernovae (SNe Ia), dataset low-redshift nearby-Hubble-flow SNe and analysis procedures to work with these heterogeneous compilations. This ``Union'' 414 SN Ia, which reduces 307 after selection cuts, includes the recent large samples from Supernova Legacy Survey ESSENCE Survey, older datasets, as well recently extended distant observed HST. A single, consistent blind procedure is used for all various subsamples, implemented that consistently weights...
The High-Z Supernova Search is an international collaboration to discover and monitor Type Ia supernovae (SNe Ia) at z > 0.2 with the aim of measuring cosmic deceleration global curvature. Our has pursued a basic understanding in nearby universe, discovering observing large sample objects developing methods measure accurate distances SNe Ia. This paper describes extension this program ≥ 0.2, outlining our search techniques follow-up program. We have devised high-throughput filters that...
We use Type Ia supernovae studied by the High-z Supernova Search Team to constrain properties of an energy component that may have contributed accelerating cosmic expansion. find for a flat geometry equation-of-state parameter unknown component, αx = Px/ρx, must be less than -0.55 (95% confidence) any value Ωm, and it is further limited < -0.60 if Ωm assumed greater 0.1. These values are inconsistent with being topological defects such as domain walls, strings, or textures. The supernova...
We develop a method for estimating the host galaxy dust extinction type Ia supernovae based on an observational coincidence first noted by Lira, who found that B-V evolution during period from 30 to 90 days after V maximum is remarkably similar all events, regardless of light-curve shape. This fact used calibrate dependence Bmax-Vmax and Vmax-Imax colors decline rate parameter Δm15(B), which can, in turn, be separately estimate extinction. Using these methods eliminate effects reddening, we...
We have coordinated Hubble Space Telescope (HST) photometry with ground-based discovery for three supernovae: Type Ia supernovae near z ≈ 0.5 (SN 1997ce, SN 1997cj) and a third event at = 0.97 1997ck). The superb spatial resolution of HST separates each supernova from its host galaxy leads to good precision in the light curves. use these curves relations between luminosity, light-curve shape, color calibrated low-z samples derive relative luminosity distances that are accurate 10% 20% 1....
We have obtained new observations of both secondary and tertiary spectrophotometric standards with the RC spectrographs CCD cameras on 1.5-m 4-m telescopes at CTIO in wavelength range 3300-7550 angstroms, as well UBV(RI)KC photometry for these stars. modified monochromatic fluxes published by Taylor (1984) according to calibration Vega provided Hayes (1985). also uned zero-point energy distribution stars matching their V synthetic magnitudes observed magnitudes. use adjusted order calculate...
We have obtained new observations of both secondary and tertiary spectrophotometric standards with the RC spectrographs CCD cameras on 1.5-m 4-m telescopes at CTIO in wavelength range 6000-10500 A. use order to calculate fluxes for Stone Baldwin (1983), as well three stars northern hemisphere from (1977). find that synthetic magnitudes calculated our spectra through IKC band agree extremely observed photometry, better than 1% average. For monochromatic fluxes, we an internal precision 0.01...
We present a new and independent determination of the local value Hubble constant based on calibration Tip Red Giant Branch (TRGB) applied to Type Ia supernovae (SNeIa). find Ho = 69.8 +/- 0.8 (+/-1.1\% stat) 1.7 (+/-2.4\% sys) km/sec/Mpc. The TRGB method is both precise accurate, parallel to, but Cepheid distance scale. Our sits midway in range defined by current tension. It agrees at 1.2-sigma level with that Planck 2018 estimate, 1.7-sigma SHoES measurement distances have been measured...
We describe observed properties of the Type Iax class supernovae (SNe Iax), consisting SNe observationally similar to its prototypical member, SN 2002cx. The currently has 25 members, and we present optical photometry and/or spectroscopy for most them. are spectroscopically Ia, but have lower maximum-light velocities (2000 ≲ |v| 8000 km s−1), typically peak magnitudes (−14.2 ⩾ MV, ≳ −18.9 mag), hot photospheres. Relative low luminosities their light-curve shape. There is a correlation...
The Carnegie Supernova Project (CSP) is a five-year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of ∼100 low-redshift Type Ia supernovae (SNe Ia) in well-defined photometric system. Here we present first release data that contains optical 35 SNe Ia, and near-infrared for subset 25 events. comprise 5559 (ugriBV) 1043 (Y JHKs) points natural system Swope telescope. Twenty-eight have pre-maximum data, 15 these, observations begin least 5 days...
With the advent of large dedicated Type Ia supernova (SN Ia) surveys, K-corrections SNe and their uncertainties have become especially important in determination cosmological parameters. While are largely driven by SN broad-band colors, it is shown here that diversity spectral features can also be important. For an individual observation, statistical errors from inhomogeneity range 0.01 (where observed rest-frame filters aligned) to 0.04 misaligned). To minimize systematic caused assumed...
We present an analysis of the diversity V-band light-curves hydrogen-rich type II supernovae. Analyzing a sample 116 supernovae, several magnitude measurements are defined, together with decline rates at different epochs, and time durations phases. It is found that magnitudes measured maximum light correlate more strongly than those other epochs: brighter supernovae generally have faster declining all epochs. find relation between rate during 'plateau' phase peak magnitudes, which has...
The Carnegie Supernova Project (CSP) was a five-year observational survey conducted at Las Campanas Observatory that obtained, among other things, high-quality light curves of ~100 low-redshift Type Ia supernovae (SNe Ia). Presented here is the second data release nearby SN photometry consisting 50 objects, with subset 45 having near-infrared follow-up observations. Thirty-three objects have optical pre-maximum coverage 15 beginning least 5 days before maximum light. In near-infrared, 27...
In providing an independent measure of the expansion history universe, Carnegie Supernova Project (CSP) has observed 71 high-z Type Ia supernovae (SNe Ia) in near-infrared bands Y and J. These can be used to construct rest-frame i-band light curves which, when compared a low-z sample, yield distance moduli that are less sensitive extinction and/or decline-rate corrections than optical. However, working with NIR photometry presents unique challenges necessitated development new set...
High-dispersion observations of the Na i D λλ5890, 5896 and K λλ7665, 7699 interstellar lines, diffuse band at 5780 Å in spectra 32 Type Ia supernovae are used as an independent means probing dust extinction. We show that extinction objects where is detected consistent with visual derived from supernova colors. This strongly suggests producing predominantly located medium host galaxies not circumstellar material associated progenitor system. One quarter display anomalously large column...
The double explosion of SN 2009ip in 2012 raises questions about our understanding the late stages massive star evolution. Here we present a comprehensive study during its remarkable rebrightenings. High-cadence photometric and spectroscopic observations from GeV to radio band obtained variety ground-based space facilities (including Very Large Array, Swift, Fermi, Hubble Space Telescope, XMM) constrain be low energy (E ∼ 1050 erg for an ejecta mass ∼0.5 M☉) asymmetric complex medium shaped...
We present an updated analysis of the intrinsic colors Type Ia supernova (SNe Ia) using latest data release Carnegie Supernova Project. introduce a new light-curve parameter very similar to stretch that is better suited for fast-declining events, and find these peculiar types can be seen as extensions population "normal" SNe Ia. With larger number objects, fit Lira relation presented along with evidence dependence on late-time slope B − V light-curves color. Using full wavelength range from...
The Public European Southern Observatory Spectroscopic Survey of Transient Objects (PESSTO) began as a public spectroscopic survey in April 2012. We describe the data reduction strategy and products which are publicly available through ESO archive Data Release 1 (SSDR1). PESSTO uses New Technology Telescope with EFOSC2 SOFI to provide optical NIR spectroscopy imaging. target supernovae transients brighter than 20.5mag for classification. Science targets then selected follow-up based on...
We present final natural system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part the first stage Carnegie Supernova Project (CSP-I). The sample consists 123 Type Ia SNe, 5 Iax 2 super-Chandrasekhar SN candidates, SNe interacting circumstellar matter, 2006bt-like events. redshifts objects range from z = 0.0037 to 0.0835; median redshift is 0.0241. For 120 (90%) these was obtained. Average...