Disk M Dwarf Luminosity Function from Hubble Space Telescope Star Counts

ABSTRACT We report on the white dwarf (WD) cooling sequence of the old globular cluster NGC 6752, which is chemically complex and hosts a blue horizontal branch. This is one of the last globular cluster WD cooling sequences accessible to imaging by the Hubble Space Telescope. Our photometry and completeness tests show that we have reached the peak of the luminosity function of the WD cooling sequence, at a magnitude mF606W = 29.4 ± 0.1, which is consistent with a formal age of ∼14 Gyr. This age is also consistent with the age from fits to the main-sequence turn-off (13–14 Gyr), reinforcing our conclusion that we observe the expected accumulation of WDs along the cooling sequence.

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Surveying the Solar Neighborhood for Brown Dwarf Companions with the ECLIPSE Discovery Mission

Symposium - International Astronomical Union ◽

10.1017/s0074180900211273 ◽

2003 ◽

Vol 211 ◽

pp. 523-524

Author(s):

Karl Stapelfeldt

Keyword(s):

Luminosity Function ◽

Hubble Space Telescope ◽

Scattered Light ◽

Solar Neighborhood ◽

Brown Dwarf ◽

Space Telescope ◽

Effective Temperatures

The proposed Eclipse Discovery mission is an optical space telescope designed to provide a thousandfold reduction in scattered light near bright stars in comparison to any Hubble Space Telescope instrument. A survey of 500 single stars within 15 pc can detect companions with absolute z magnitude of 22 at separations > 10 AU in most of the targets. Spectrophotometry of CH4 and H2O bands between 0.8-1.0 μm can be used to derive the effective temperatures of the objects. The ECLIPSE brown dwarf survey would directly measure the luminosity function of brown dwarf companions down to ~20 Jupiter masses, providing a crucial comparison with field objects.

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[ITAL]Hubble Space Telescope[/ITAL] Observations of the Central-Cusp Globular Cluster NGC 6752: the Effect of Binary Stars on the Luminosity Function in the Core

The Astrophysical Journal ◽

10.1086/311911 ◽

1999 ◽

Vol 513 (1) ◽

pp. L33-L36 ◽

Cited By ~ 9

Author(s):

Eric P. Rubenstein ◽

Charles D. Bailyn

Keyword(s):

Globular Cluster ◽

Binary Stars ◽

Luminosity Function ◽

Hubble Space Telescope ◽

Space Telescope ◽

The Core ◽

Central Cusp

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PROBING VERY BRIGHT END OF GALAXY LUMINOSITY FUNCTION AT z ≳ 7 USING HUBBLE SPACE TELESCOPE PURE PARALLEL OBSERVATIONS

The Astrophysical Journal ◽

10.1088/2041-8205/728/1/l22 ◽

2011 ◽

Vol 728 (1) ◽

pp. L22 ◽

Cited By ~ 68

Author(s):

Haojing Yan ◽

Lin Yan ◽

Michel A. Zamojski ◽

Rogier A. Windhorst ◽

Patrick J. McCarthy ◽

...

Keyword(s):

Luminosity Function ◽

Hubble Space Telescope ◽

Space Telescope ◽

Galaxy Luminosity Function

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X-Ray Binaries in M51 I: Catalog and Statistics

The Astrophysical Journal ◽

10.3847/1538-4357/ac22ac ◽

2021 ◽

Vol 922 (2) ◽

pp. 178

Author(s):

Jared R. Rice ◽

Blagoy Rangelov ◽

Andrea Prestwich ◽

Rupali Chandar ◽

Luis Bichon ◽

...

Keyword(s):

Optical Properties ◽

Data Analysis ◽

Luminosity Function ◽

Binary Systems ◽

Hubble Space Telescope ◽

Archival Data ◽

Optical Counterpart ◽

Space Telescope ◽

X Ray ◽

X Ray Binaries

Abstract We used archival data from the Chandra X-ray Observatory (Chandra) and the Hubble Space Telescope, to identify 334 candidate X-ray binary systems and their potential optical counterparts in the interacting galaxy pair NGC 5194/5195 (M51). We present the catalog and data analysis of X-ray and optical properties for those sources, from the deep 892 ks Chandra observations, along with the magnitudes of candidate optical sources as measured in the 8.16 ks Hubble Space Telescope observations. The X-ray luminosity function of the X-ray sources above a few times 1036 erg s−1 follows a power law N ( > L X , b ) ∝ L X , b 1 − α with α = 1.65 ± 0.03. Approximately 80% of sources are variable over a 30 day window. Nearly half of the X-ray sources (173/334) have an optical counterpart within 0.″5.

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