flash spectroscopy
Recently Published Documents


TOTAL DOCUMENTS

63
(FIVE YEARS 2)

H-INDEX

21
(FIVE YEARS 0)

2022 ◽  
Vol 924 (1) ◽  
pp. 15
Author(s):  
W. V. Jacobson-Galán ◽  
L. Dessart ◽  
D. O. Jones ◽  
R. Margutti ◽  
D. L. Coppejans ◽  
...  

Abstract We present panchromatic observations and modeling of supernova (SN) 2020tlf, the first normal Type II-P/L SN with confirmed precursor emission, as detected by the Young Supernova Experiment transient survey. Pre-SN activity was detected in riz-bands at −130 days and persisted at relatively constant flux until first light. Soon after discovery, “flash” spectroscopy of SN 2020tlf revealed narrow, symmetric emission lines that resulted from the photoionization of circumstellar material (CSM) shed in progenitor mass-loss episodes before explosion. Surprisingly, this novel display of pre-SN emission and associated mass loss occurred in a red supergiant (RSG) progenitor with zero-age main-sequence mass of only 10–12 M ⊙, as inferred from nebular spectra. Modeling of the light curve and multi-epoch spectra with the non-LTE radiative-transfer code CMFGEN and radiation-hydrodynamical code HERACLES suggests a dense CSM limited to r ≈ 1015 cm, and mass-loss rate of 10−2 M ⊙ yr−1. The luminous light-curve plateau and persistent blue excess indicates an extended progenitor, compatible with an RSG model with R ⋆ = 1100 R ⊙. Limits on the shock-powered X-ray and radio luminosity are consistent with model conclusions and suggest a CSM density of ρ < 2 × 10−16 g cm−3 for distances from the progenitor star of r ≈ 5 × 1015 cm, as well as a mass-loss rate of M ̇ < 1.3 × 10 − 5 M ☉ yr − 1 at larger distances. A promising power source for the observed precursor emission is the ejection of stellar material following energy disposition into the stellar envelope as a result of gravity waves emitted during either neon/oxygen burning or a nuclear flash from silicon combustion.


2020 ◽  
Vol 11 (21) ◽  
pp. 5511-5525
Author(s):  
Megan S. Lazorski ◽  
Igor Schapiro ◽  
Ross S. Gaddie ◽  
Ammon P. Lehnig ◽  
Mihail Atanasov ◽  
...  

Quantum chemical calculations and laser flash spectroscopy probe spin-dynamics of the photoinduced electron transfer mechanism in two donor–acceptor bisphenanthrolinecopper(i) species, marking the influence of spin on solar energy conversion schemes.


2016 ◽  
Vol 818 (1) ◽  
pp. 3 ◽  
Author(s):  
D. Khazov ◽  
O. Yaron ◽  
A. Gal-Yam ◽  
I. Manulis ◽  
A. Rubin ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-3 ◽  
Author(s):  
Fuat Bayrakceken ◽  
Korkut Yegin

Spectroscopically pure fused silica has been used in many applications ranging from optoelectronics and optical fibers to laser flash spectroscopy. Although ultraviolet light irradiated optical absorption spectra and coherence fluorescence of silicon dioxide have been studied in the past, we present discrete absorption and resonance coherent fluorescence line of silicon dioxide which were recorded photographically at 288.2 nm. This discrete fluorescence is observed at room temperature using high photon flux (1024photon/pulse) excitation spectroscopy.


2007 ◽  
Author(s):  
William George Breiland ◽  
William Dodd Reinhart ◽  
Paul Albert Miller ◽  
Justin L Brown ◽  
Thornhill, Tom Finley, III (, ◽  
...  

Biochemistry ◽  
1999 ◽  
Vol 38 (48) ◽  
pp. 16016-16023 ◽  
Author(s):  
Dmitry Zaslavsky ◽  
Irina A. Smirnova ◽  
Peter Brzezinski ◽  
Kyoko Shinzawa-Itoh ◽  
Shinya Yoshikawa ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document