Science Archives Publication System

SN Hunt 248: a super-Eddington outburst from a massive cool hypergiant

DOI: 10.1093/mnras/stu2541 Bibcode: 2015MNRAS.447.1922M

Van Dyk, Schuyler D.; Filippenko, Alexei V.; Smith, Nathan +8 more

We present observations of SN Hunt 248, a new supernova (SN) impostor in NGC 5806, which began a multistage outburst in 2014 May. The `2014a' discovery brightening exhibited an absolute magnitude of M ≈ -12 and the spectral characteristics of a cool, dense outflow, including P Cygni lines of Fe II, H I, and Na I, and line blanketing from metals. T…

2015 • Monthly Notices of the Royal Astronomical Society

eHST 37

Hubble Space Telescope Near-Ultraviolet Spectroscopy of Bright CEMP-s Stars

DOI: 10.1088/0004-637X/812/2/109 Bibcode: 2015ApJ...812..109P

Smith, Verne V.; Beers, Timothy C.; Placco, Vinicius M. +14 more

We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the bright carbon-enhanced metal-poor (CEMP) stars HD 196944 (V=8.40, [Fe/H] = -2.41) and HD 201626 (V=8.16, [Fe/H] = -1.51), based on data acquired with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope. Both of these stars be…

2015 • The Astrophysical Journal

eHST 37

The heavy ion diffusion region in magnetic reconnection in the Earth's magnetotail

DOI: 10.1002/2015JA020982 Bibcode: 2015JGRA..120.3535L

Kistler, L. M.; Mouikis, C. G.; Wang, S. +3 more

While the plasma in the Earth's magnetotail predominantly consists of protons and electrons, there are times when a significant amount of oxygen is present. When magnetic reconnection occurs, the behavior of these heavy ions can be significantly different from that of the protons, due to their larger gyroradius. In this study, we investigate the h…

2015 • Journal of Geophysical Research (Space Physics)

Cluster 37

Modeling of Reflective Propagating Slow-mode Wave in a Flaring Loop

DOI: 10.1088/0004-637X/813/1/33 Bibcode: 2015ApJ...813...33F

Fang, X.; Xia, C.; Van Doorsselaere, T. +2 more

Quasi-periodic propagating intensity disturbances have been observed in large coronal loops in extreme ultraviolet images over a decade, and are widely accepted to be slow magnetosonic waves. However, spectroscopic observations from Hinode/EIS revealed their association with persistent coronal upflows, making this interpretation debatable. We perf…

2015 • The Astrophysical Journal

SOHO 37

Spectroscopic constraints on CH₃OH formation: CO mixed with CH₃OH ices towards young stellar objects

DOI: 10.1093/mnras/stv1987 Bibcode: 2015MNRAS.454..531P

Pontoppidan, K. M.; Blake, G. A.; Boogert, A. C. A. +3 more

The prominent infrared absorption band of solid CO - commonly observed towards young stellar objects (YSOs) - consists of three empirically determined components. The broad `red component' (2136 cm^-1, 4.681 µm) is generally attributed to solid CO mixed in a hydrogen-bonded environment. Usually, CO embedded in the abundantly presen…

2015 • Monthly Notices of the Royal Astronomical Society

ISO 37

Origin of the X-ray off-states in Vela X-1

DOI: 10.1051/0004-6361/201321414 Bibcode: 2015A&A...575A..58M

Walter, R.; Manousakis, A.

Context. Vela X-1 is the prototype of the classical super-giant high mass X-ray binary systems. Recent continuous and long monitoring campaigns revealed a large hard X-rays variability amplitude with strong flares and off-states. This activity has been interpreted by invoking clumpy stellar winds and/or magnetic gating mechanisms.
Aims: We in…

2015 • Astronomy and Astrophysics

INTEGRAL 37

Deep Optical Images of Malin 1 Reveal New Features

DOI: 10.1088/2041-8205/815/2/L29 Bibcode: 2015ApJ...815L..29G

Infante, Leopoldo; Galaz, Gaspar; Suc, Vincent +4 more

We present Megacam deep optical images (g and r) of Malin 1 obtained with the 6.5 m Magellan/Clay telescope, detecting structures down to ∼28 B mag arcsec^-2. In order to enhance galaxy features buried in the noise, we use a noise reduction filter based on the total generalized variation regularizator. This method allows us to detect and…

2015 • The Astrophysical Journal

eHST 37

A new isolated dSph galaxy near the Local Group

DOI: 10.1093/mnrasl/slu181 Bibcode: 2015MNRAS.447L..85K

Rizzi, L.; Karachentsev, I. D.; Makarova, L. N. +2 more

Observations of the highly isolated dwarf spheroidal galaxy KKs 3 = [KK2000] 03 with the Hubble Space Telescope Advanced Camera for Surveys are presented. We measured the galaxy distance of 2.12 ± 0.07 Mpc using the tip of red giant branch method. The total blue absolute magnitude of the galaxy is estimated as M_B = -10.8 mag. We briefly…

2015 • Monthly Notices of the Royal Astronomical Society

eHST 37

Recurrent flares in active region NOAA 11283

DOI: 10.1051/0004-6361/201525887 Bibcode: 2015A&A...582A..55R

Romoli, M.; Vecchio, A.; Pietropaolo, E. +21 more

Context. Flares and coronal mass ejections (CMEs) are solar phenomena that are not yet fully understood. Several investigations have been performed to single out their related physical parameters that can be used as indices of the magnetic complexity leading to their occurrence.
Aims: In order to shed light on the occurrence of recurrent flar…

2015 • Astronomy and Astrophysics

SOHO 37

Analysis of HST/COS spectra of the bare C-O stellar core H1504+65 and a high-velocity twin in the Galactic halo

DOI: 10.1051/0004-6361/201527261 Bibcode: 2015A&A...584A..19W

Rauch, T.; Werner, K.

H1504+65 is an extremely hot white dwarf (effective temperature T_eff = 200 000 K) with a carbon-oxygen dominated atmosphere devoid of hydrogen and helium. This atmospheric composition was hitherto unique among hot white dwarfs (WDs), and it could be related to recently detected cooler WDs with C or O dominated spectra…

2015 • Astronomy and Astrophysics

eHST 37