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Semantic Scholar Open Access 2017 11 sitasi

Project 1640 Observations of Brown Dwarf GJ 758 B: Near-infrared Spectrum and Atmospheric Modeling

R. Nilsson A. Veicht P. A. Godfrey E. Rice J. Aguilar +55 lainnya
Lihat Sumber DOI

Abstrak

The nearby Sun-like star GJ 758 hosts a cold substellar companion, GJ 758 B, at a projected separation of ≲30 au, previously detected in high-contrast multi-band photometric observations. In order to better constrain the companion’s physical characteristics, we acquired the first low-resolution (R ∼ 50) near-infrared spectrum of it using the high-contrast hyperspectral imaging instrument Project 1640 on Palomar Observatory’s 5 m Hale telescope. We obtained simultaneous images in 32 wavelength channels covering the Y, J, and H bands (∼952–1770 nm), and used data processing techniques based on principal component analysis to efficiently subtract chromatic background speckle-noise. GJ 758 B was detected in four epochs during 2013 and 2014. Basic astrometric measurements confirm its apparent northwest trajectory relative to the primary star, with no clear signs of orbital curvature. Spectra of SpeX/IRTF observed T dwarfs were compared to the combined spectrum of GJ 758 B, with χ2 minimization suggesting a best fit for spectral type T7.0 ± 1.0, but with a shallow minimum over T5–T8. Fitting of synthetic spectra from the BT-Settl13 model atmospheres gives an effective temperature Teff = 741 ± 25 K and surface gravity dex (cgs). Our derived best-fit spectral type and effective temperature from modeling of the low-resolution spectrum suggest a slightly earlier and hotter companion than previous findings from photometric data, but do not rule out current results, and confirm GJ 758 B as one of the coolest sub-stellar companions to a Sun-like star to date.

Topik & Kata Kunci

Physics

Penulis (60)

R

R. Nilsson

A

A. Veicht

P

P. A. Godfrey

E

E. Rice

J

J. Aguilar

L

L. Pueyo

L

L. Roberts

R

R. Oppenheimer

D

D. Brenner

S

S. Luszcz-Cook

E

E. Bacchus

C

C. Beichman

R

R. Burruss

E

E. Cady

R

R. Dekany

R

R. Fergus

L

L. Hillenbrand

S

S. Hinkley

D

D. King

T

T. Lockhart

I

I. Parry

A

A. Sivaramakrishnan

R

R. Soummer

G

G. Vasisht

C

C. Zhai

N

N. Department

A

A. History

N

New York.

N

Ny

U

Usa

D

D. O. Astronomy

S

S. University

S

Stockholm

S

Sweden.

C

C. I. O. Technology.

P

Pasadena

C

Ca

C

City University of New York

D

Department of Engineering SciencePhysics

C

College of Staten Island

S

Staten Island

D

D. Physics

A

Astronomy

T

T. J. H. University

B

Baltimore.

M

Md.

S

Space Telescope Science Institute

J

Jet propulsion Laboratory

I

I. O. Astronomy

C

Cambridge University

C

Cambridge

U

UK.

C

Caltech Optical Observatories

N

Nasa Lunar Science Institute

D

Department of Materials Science

C

C. I. O. M. Sciences

N

N. University

S

S. O. Physics

U

U. Exeter

E

Exeter

Format Sitasi

APA MLA BibTeX
Nilsson, R., Veicht, A., Godfrey, P.A., Rice, E., Aguilar, J., Pueyo, L. et al. (2017). Project 1640 Observations of Brown Dwarf GJ 758 B: Near-infrared Spectrum and Atmospheric Modeling. https://doi.org/10.3847/1538-4357/aa643c

Akses Cepat

Lihat di Sumber doi.org/10.3847/1538-4357/aa643c
Informasi Jurnal
Tahun Terbit
2017
Bahasa
en
Total Sitasi
11×
Sumber Database
Semantic Scholar
DOI
10.3847/1538-4357/aa643c
Akses
Open Access ✓