SDSS J1416+1348: Comparison
View Latest Version
Please note this is a comparison between Version 2 by Camila Xu and Version 1 by Camila Xu.

Coordinates: 14h 16m 24.08s, +13° 48′ 26.7″ SDSS J1416+1348 (full designation is SDSS J141624.08+134826.7) is a nearby wide binary system of two brown dwarfs, located in constellation Boötes. The system consists of L-type component A and T-type component B.

  • 24.08s
  • binary system
  • j141624.08134826.7

1. Discovery

Component A was discovered in late 2009[1] from a search of Sloan Digital Sky Survey (SDSS) Data Release 7, an astronomical survey conducted at Apache Point Observatory in New Mexico, United States . It has two discovery papers: Bowler et al., 2009[2] and Schmidt et al., 2009.[3]

Component B was discovered in early 2010 from UKIDSS Large Area Survey (ULAS) Data Release 5[4] & 6,[5] an astronomical survey conducted on the United Kingdom Infrared Telescope (UKIRT) on Mauna Kea in Hawaii. It has also two discovery papers: Burningham et al., 2010[4] and Scholz, 2010.[5] Burningham et al. discovered the whole system (independently of Bowler et al. and Schmidt et al.[4]) by cross-matching the ULAS DR5 against SDSS DR7,[4] and Scholz discovered component B by inspecting the UKIDSS finding charts around already found component A.[5]

2. Distance

In 2012 was published the first relatively precise parallax of SDSS J1416+1348, measured at the Canada-France-Hawaii Telescope under The Hawaii Infrared Parallax Program: 109.9 ± 1.8 mas, corresponding to a distance 9.10 ± 0.15 pc (29.7 ± 0.5 ly).[6] (Although, two parallaxes with large errors was previously published by Bowler et al.[2] and Scholz[5]).

SDSS J1416+1348 distance estimates
Source Parallax, mas Distance, pc Distance, ly Ref.
Bowler et al., 2009 107 ± 34[7] 9.3+4.4−2.3 30.5+14.2−7.6 [2]
Bowler et al., 2009   8.4 ± 1.9 27.4 ± 6.2 [2]
Schmidt et al., 2009   8.0 ± 1.6 26.1 ± 5.2 [3]
Burningham et al., 2010   5–15 16–49 [4]
Scholz, 2010   7.9 ± 1.7 25.8 ± 5.5 [5]
Burgasser et al., 2010   10.6+3.0−2.8 34.6+9.8−9.1 [8]
Cushing et al., 2010   9.7 ± 0.1[9] 31.6 ± 0.3[9] [10]
The Hawaii Infrared Parallax Program

(Dupuy & Liu, 2012)		 109.9 ± 1.8 9.10 ± 0.15 29.7 ± 0.5 [6]

Non-trigonometric distance estimates are marked in italic. The best estimate is marked in bold.

3. Space Motion

SDSS J1416+1348 has proper motion 165 mas·yr−1 with position angle 32 degrees, indicating motion in north-east direction on the sky. Corresponding right ascension and declination components of proper motion are 88.0 ± 2.8 mas/yr and 139.9 ± 1.3 mas/yr, respectively.[3] At distance 29.7 ly (assuming parallax 109.0 ± 1.8 mas),[6] corresponding tangential velocity is 7.1 km/s. Radial velocity of SDSS J1416+1348 is -42.2 ± 5.1 km/s.[3] (Negative radial velocity value indicates that SDSS J1416+1348 is now approaching to us). Total velocity of SDSS J1416+1348 relatively to Solar system is 42.8 km/s.

SDSS J1416+1348 space motions estimates

Source μ,

mas/yr		 P. A.,

°		 μRA,

mas/yr		 μDEC,

mas/yr		 Vtan,

km/s[11]		 Vr,

km/s		 Ref.
Bowler et al., 2009 151 ± 8 33 ± 4 82 127 6.5 –38 ± 10 [2]
Schmidt et al., 2009 165 32 88.0 ± 2.8 139.9 ± 1.3 7.1 -42.2 ± 5.1 [3]
Scholz, 2010 163 32 86.2 ± 2.6 138.8 ± 2.6 7.1   [5]
SIMBAD 165 32 88 ± 3 140 ± 2 7.1 -87 ± 33 [12]
Dupuy & Liu, 2012 161.3 ± 2.8 36.1 ± 1.2 95.1 ± 3.0 130.3 ± 3.0 7.1   [6]

The most accurate estimates are marked in bold.

Space motion of SDSS J1416+1348 indicates that it is member of Galactic thin disk population.[2][3][5]

3.1. Solar Encounter

Since SDSS J1416+1348 moves much faster in radial direction than in tangential direction, and radial velocity is negative, this brown dwarf system should pass Solar system in future at much smaller distance, than today's distance. Proper motion and radial velocity values from Schmidt et al., 2009 and parallax from Dupuy & Liu, 2012, assuming motion with constant velocity along straight line, yield minimal distance 4.9 ly circa year 207100.

Solar encounter chronology, assuming motion with constant velocity in a straight line relatively Solar system:[13]

Date Distance,

ly		 Constellation Note
759300 BC 137.96 Virgo/Boötes transition to constellation Boötes
493000 BC 100 Boötes approach to a distance of 100 ly
141600 BC 50 Boötes approach to a distance of 50 ly
300 BC 30 Boötes approach to a distance of 30 ly
2000 29.68 Boötes near present time
71300 20 Boötes approach to a distance of 20 ly
107900 15 Boötes approach to a distance of 15 ly
146200 10 Boötes approach to a distance of 10 ly
162900 8.01 Boötes/Corona Borealis transition to constellation Corona Borealis
168000 7.46 Corona Borealis/Boötes transition to constellation Boötes
170600 7.18 Boötes/Hercules transition to constellation Hercules
186500 5.76 Hercules/Draco transition to constellation Draco
202000 5 Draco approach to a distance of 5 ly
203600 4.97 Draco/Cygnus transition to constellation Cygnus
207100 4.95 Cygnus minimal distance
207600 4.95 Cygnus/Cepheus transition to constellation Cepheus
212200 5 Cepheus removal to a distance of 5 ly
212800 5.01 Cepheus/Cygnus transition to constellation Cygnus
215300 5.08 Cygnus /Cepheus transition to constellation Cepheus
215600 5.09 Cepheus/Lacerta transition to constellation Lacerta
222500 5.41 Lacerta/Andromeda transition to constellation Andromeda
262300 9.3 Andromeda/Pisces transition to constellation Pisces
268000 10 Pisces removal to a distance of 10 ly
306400 15 Pisces removal to a distance of 15 ly
343000 20 Pisces removal to a distance of 20 ly
410500 29.44 Pisces/Cetus transition to constellation Cetus
414500 30 Cetus removal to a distance of 30 ly
507000 43.07 Cetus transition to southern hemisphere
555900 50 Cetus removal to a distance of 50 ly
907200 100 Cetus removal to a distance of 100 ly

4. System's Properties

SDSS J1416+1348 is an old system (age estimates: >0.8 Gyr,[3] ~10 Gyr,[4] ~5 Gyr,[5] 2–10 Gyr,[8] >3.2 Gyr[10]), and, probably, possesses low metallicity.[4] Its two components are separated at angular distance 9.81 arcsec, corresponding to a projected separation 89.3 ± 1.5 a. u.[6] The system's orbit semi-major axis estimate is 104+28−72 a. u.[6]

4.1. Component A

The primary (brighter) component (SDSS J141624.08+134826.7 is mainly its designation; also known as SDSS J1416+13A) is a brown dwarf of spectral type sdL7,[14] or L6,[2][5][6] or L5,[3] or d/sdL7.[4] It has unusually blue near-infrared J−KS color.[3][4][5][8] According to Cushing et al. 2010, its peculiar spectrum is primarily a result of thin condensate clouds, and also vertical mixing occurs in its atmosphere.[10] However, in Burgasser et al., 2010 it was suggested that its (as well as component's B) peculiarities arise from age or metallicity, rather than cloud properties alone (since both A and B components have common peculiarities).[8]

4.2. Component B

The secondary (fainter) component (ULAS J141623.94+134836.3, abbreviated to ULAS J1416+1348, also known as SDSS J1416+13B) is a brown dwarf of spectral type T7.5,[8][15][16] or T7.5p.[4][6] It has unusually extremely blue near-infrared color H−K,[4] very red optical-to-near-infrared color (z−Y > +2.3 and z−J > +3.1),[5] and extremely red color H−[4.5] = 4.86 ± 0.04[4] (it was suggested, that the latter may be explained by presence of a cooler unresolved companion to SDSS J1416+13B).[4] Also, its spectrum indicates high surface gravity and/or subsolar metallicity.[8]

References

  1. Date of arXiv preprint. The articles was published in journals in early 2010.
  2. Bowler, Brendan P.; Liu, Michael C.; Dupuy, Trent J. (2010). "SDSS J141624.08+134826.7: A Nearby Blue L Dwarf From the Sloan Digital Sky Survey". The Astrophysical Journal 710 (1): 45–50. doi:10.1088/0004-637X/710/1/45. Bibcode: 2010ApJ...710...45B.  https://dx.doi.org/10.1088%2F0004-637X%2F710%2F1%2F45
  3. Schmidt, Sarah J.; West, Andrew A.; Burgasser, Adam J.; Bochanski, John J.; Hawley, Suzanne L. (2010). "Discovery of an Unusually Blue L Dwarf Within 10 pc of the Sun". The Astronomical Journal 139 (3): 1045–1050. doi:10.1088/0004-6256/139/3/1045. Bibcode: 2010AJ....139.1045S.  https://dx.doi.org/10.1088%2F0004-6256%2F139%2F3%2F1045
  4. Burningham, Ben; Leggett, S. K.; Lucas, P. W.; Pinfield, D. J.; Smart, R. L.; Day-Jones, A. C. et al. (2010). "The discovery of a very cool binary system". Monthly Notices of the Royal Astronomical Society 404 (4): 1952–1961. doi:10.1111/j.1365-2966.2010.16411.x. Bibcode: 2010MNRAS.404.1952B.  https://dx.doi.org/10.1111%2Fj.1365-2966.2010.16411.x
  5. Scholz, R.-D. (2010). "ULAS J141623.94+134836.3 - a faint common proper motion companion of a nearby L dwarf. Serendipitous discovery of a cool brown dwarf in UKIDSS DR6". Astronomy and Astrophysics 510: L8. doi:10.1051/0004-6361/201014078. Bibcode: 2010A&A...510L...8S.  https://dx.doi.org/10.1051%2F0004-6361%2F201014078
  6. nullSchmidt, Sarah J.; West, Andrew A.; Burgasser, Adam J.; Bochanski, John J.; Hawley, Suzanne L. (2010). "Discovery of an Unusually Blue L Dwarf Within 10 pc of the Sun". The Astronomical Journal 139 (3): 1045–1050. doi:10.1088/0004-6256/139/3/1045. Bibcode: 2010AJ....139.1045S.
  7. Relative parallax.
  8. Burgasser, Adam J.; Looper, Dagny; Rayner, John T. (2010). "ULAS J141623.94+134836.3: A Blue T Dwarf Companion to a Blue L Dwarf". The Astronomical Journal 139 (6): 2448–2454. doi:10.1088/0004-6256/139/6/2448. Bibcode: 2010AJ....139.2448B.  https://dx.doi.org/10.1088%2F0004-6256%2F139%2F6%2F2448
  9. The error does not include any errors in temperature and surface gravity and therefore is actually larger.
  10. Cushing, Michael C.; Saumon, D.; Marley, Mark S. (2010). "SDSS J141624.08+134826.7: Blue L dwarfs and Non-equilibrium Chemistry". The Astronomical Journal 140 (5): 1428–1432. doi:10.1088/0004-6256/140/5/1428. Bibcode: 2010AJ....140.1428C.  https://dx.doi.org/10.1088%2F0004-6256%2F140%2F5%2F1428
  11. Assuming parallax 109.9 ± 1.8 mas.
  12. "2MASS J14162408+1348263 -- Star". SIMBAD. Centre de Données astronomiques de Strasbourg. http://simbad.cfa.harvard.edu/simbad/sim-id?submit=display&bibdisplay=refsum&bibyear1=1850&bibyear2=%24currentYear&Ident=%405197735&Name=2MASS+J14162408%2B1348263#lab_bib. Retrieved 2012-05-19. 
  13. Actually, galactic orbits may be considered as approximately straight lines only on a scale much smaller than theirs sizes.
  14. Kirkpatrick, J. Davy; Looper, Dagny L.; Burgasser, Adam J.; Schurr, Steven D.; Cutri, Roc M.; Cushing, Michael C. et al. (2010). "Discoveries from a Near-infrared Proper Motion Survey Using Multi-epoch Two Micron All-Sky Survey Data". The Astrophysical Journal Supplement 190 (1): 100–146. doi:10.1088/0067-0049/190/1/100. Bibcode: 2010ApJS..190..100K. http://authors.library.caltech.edu/20570/1/Kirkpatrick2010p11580Astrophys_J_Suppl_S.pdf. 
  15. Kirkpatrick, J. Davy; Gelino, Christopher R.; Cushing, Michael C.; Mace, Gregory N.; Griffith, Roger L.; Skrutskie, Michael F.; Marsh, Kenneth A.; Wright, Edward L. et al. (2012). "Further Defining Spectral Type "Y" and Exploring the Low-mass End of the Field Brown Dwarf Mass Function". The Astrophysical Journal 753: 156. doi:10.1088/0004-637X/753/2/156. Bibcode: 2012ApJ...753..156K.  https://dx.doi.org/10.1088%2F0004-637X%2F753%2F2%2F156
  16. Kirkpatrick, J. Davy; Cushing, Michael C.; Gelino, Christopher R.; Griffith, Roger L.; Skrutskie, Michael F.; Marsh, Kenneth A. et al. (2011). "The First Hundred Brown Dwarfs Discovered by the Wide-field Infrared Survey Explorer (WISE)". The Astrophysical Journal Supplement 197 (2): 19. doi:10.1088/0067-0049/197/2/19. Bibcode: 2011ApJS..197...19K.  https://dx.doi.org/10.1088%2F0067-0049%2F197%2F2%2F19
More
© Text is available under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)
ScholarVision Creations
Feedback