The NIRSPEC Brown Dwarf Spectroscopic Survey (BDSS)

Paper I: McLean, I.S., McGovern, M.R., Burgasser, A.J., Kirkpatrick, J.D., Prato, L., & Kim, S.S. 2003, ApJ, 596, 561

Paper II: McLean, I.S., Prato, L., McGovern, M.R., Burgasser, A.J., Kirkpatrick, J.D., Rice, E.L., & Kim, S.S. 2007, ApJ, 658, 1217

Please cite the appropriate above references if you use or display these data in your publications or presentations.

Data Archive

Announcements

Poster presented at 209th AAS Meeting
JPEG

UCLA Press Release, 3 September 2003
PDF

Introduction to the BDSS
MS PowerPoint  HTML export


NIRSPEC

NIRSPEC positioned at the KECK II Nasymth platform

Introduction - BDSS

The Brown Dwarf Spectroscopic Survey (BDSS), established in 1998 by Dr. Ian McLean in collaboration with Dr. J. Davy Kirkpatrick at IPAC, is designed to study near-infrared moderate-to-high resolution spectra for a large sample of low-mass stars and sub-stellar mass objects in the M and newly defined L and T dwarf classes. The BDSS was initiated following the successful first light commissioning of the Keck-II Near-Infrared Spectrometer (NIRSPEC) in April 1999. The goals of the BDSS are:

  1. obtain a uniform set of moderate resolution (R~ 2,000) NIR spectra for a large sample of very low-mass stars and brown dwarfs to examine general spectral properties and facilitate comparisons with theoretical spectral energy distributions;
  2. obtain a set of high resolution spectra (R~20,000) for detailed comparison of individual spectral features with model atmospheres; and
  3. monitor selected sources for Doppler shifts induced by unresolved binary companions.

For a description of NIRSPEC see:

McLean, I.S., et al. 1998, Proc. SPIE, 3354, 566 (PDF)
McLean, I.S., et al. 2000, Proc. SPIE, 4008, 1048 (PDF)

Description of Low-Resolution Data Products

Filter Configurations All data products were obtained with NIRSPEC in its low resolution (R~2000) mode with the 42x0.38 arcsecond (2 pixel) slit in place. Six filters (NIRSPEC-1 through NIRSPEC-6) give overlapping wavelength coverage from 0.96 - 2.31 microns. The table on the right lists the seven instrumental configurations we have used and their effective wavelength range of importance to the survey. Note: The NIRSPEC-6 is a broad H+K filter centered at 1.925 microns with a bandwidth of 0.75 microns. Since the entire NIRSPEC-6 bandwidth cannot be simultaneously observed on the detector, two configurations, N6a and N6b, are used to obtain the long wavelength half of the H-band and the K-band, respectively. NIRSPEC-5 (essentially H-band) was used only for one observation of the T8 dwarf 2MASS 0415-09.

The table below lists the sample of low mass stars and brown dwarfs included in our survey. The observing strategy for these objects was to obtain a 300s exposure with the source at each of two positions separated by ~20" along the 0.38" slit. Most objects were observed in an ABBA pattern giving total integration time of 20 minutes per grating/filter configuration. For fainter objects (J~16) this procedure was repeated to maintain a signal-to-noise ratio of at least 20:1 per resolution element over the majority of the spectral region observed. Reduction of the spectra was accomplished using REDSPEC, software designed and developed primarily for NIRSPEC data reduction. Data from filters NIRSPEC-3 through NIRSPEC-6 were combined to create a 1.14-2.31 micron composite spectrum. In some cases the shorter wavelength end was extended out to 0.96 microns with the inclusion of data from the NIRSPEC-1 & 2 filters. Composite spectra were flux calibrated (in Flambda units) using 2MASS photometry, following the prescription of McLean et al. (2001). See paper for details concerning the observing strategy and data reduction process.

Data products can be downloaded individually from the table of objects given below or in groups found the next section. Individual data files contain six lines of introductory text followed by two columns of wavelength (microns) in the first and normalized flambda in the second. Composite spectra follow the same prescription except the second column is replaced by flux calibrated data (W m^-2 um^-1) using 2MASS photometry.

Description of High-Resolution Data Products

NIRSPEC-3 Echelle Configurations All high-resolution data products were obtained with NIRSPEC in its high-resolution (R~20,000) mode with the 12 arcsecond by 0.432 arcsecond (3 pixel) slit in place except in the case of 2MASS 1507-16, for which the 0.576 arcsecond slit (4 pixels) was used because of poor seeing. The NIRSPEC-3 filter, approximating standard J-band coverage, was used for all observations. The table on the left lists the effective wavelength coverage of each echelle order for the given instrument settings.

The table below lists the sample of low mass stars and brown dwarfs included in our high-resolution survey. The observing strategy for these objects was to obtain a 300-second or 600-second exposure (40 seconds by 3 coadds for Wolf 359 and 360 seconds for 2MASS 0746+20) with the source at each of two positions separated by seven arcseconds along the 12-arcsecond-long slit. Most objects were observed in an ABBA pattern giving total integration time of 20-40 minutes. For fainter objects (J~16) this procedure was repeated to maintain a signal-to-noise ratio of at least 20:1 per resolution element over the majority of the spectral region observed. Reduction of the spectra was accomplished using REDSPEC, software designed and developed primarily for NIRSPEC data reduction. See paper for details concerning the observing strategy and data reduction process.

Data products can be downloaded individually from the table of objects given below or in groups found the next section. Individual data files contain six lines of introductory text followed by two columns of wavelength (microns) in the first and flux (normalized within each order) in the second.

Download Data Products

Download entire BDSS low-resolution archive: Gzip Archive , WinZip
Groups - Filter Sets
Download entire N1 filter data set: Gzip Archive , WinZip
Download entire N2 filter data set: Gzip Archive , WinZip
Download entire N3 filter data set: Gzip Archive , WinZip
Download entire N4 filter data set: Gzip Archive , WinZip
Download entire N6a filter data set: Gzip Archive , WinZip
Download entire N6b filter data set: Gzip Archive , WinZip
Download entire flux calibrated composite data:
Download flux calibrated JHKs <1.140-2.315 um> data set: Gzip Archive , WinZip
Download flux calibrated zJHKs <0.960-2.315 um> data set: Gzip Archive , WinZip
Download all flux calibrated composite data: Gzip Archive , WinZip
Download entire BDSS high-resolution archive: Gzip Archive , WinZip
Groups - Echelle Orders
Download entire order 58 data set: Gzip Archive , WinZip
Download entire order 59 data set: Gzip Archive , WinZip
Download entire order 60 data set: Gzip Archive , WinZip
Download entire order 61 data set: Gzip Archive , WinZip
Download entire order 62 data set: Gzip Archive , WinZip
Download entire order 63 data set: Gzip Archive , WinZip
Download entire order 64 data set: Gzip Archive , WinZip
Download entire order 65 data set: Gzip Archive , WinZip


Low-Resolution Data Products

Type

Coverage

Options

/>

D -- Link to individual ascii data file (flux vs. wavelength).

P -- Link to individual postscript plot of data.


All coordinates and JHKs photometry are from the 2MASS All-Sky Data Release. Magnitude uncertainties can be obtained from Table 2 of McLean et al. (2003).
Spectral types for M dwarfs based on the classification scheme of Kirkpatrick, Henry, & McCarthy (1991) and Kirkpatrick, Henry, & Simons (1995).
Spectral types for L dwarfs based on the Kirkpatrick optical classification scheme.
Spectral types for T dwarfs based on the Burgasser near-infrared classification scheme.

For additional information regarding objects in this archive see Davy Kirkpatrick's L & T Dwarf Archive.


High-Resolution Data Products

 D  -- Link to individual ascii data file (flux vs. wavelength).
 P  -- Link to postscript plot of all echelle orders.
Type Object Name   RA (2000)    Dec (2000)  J    Itime (s)    Avg SNR BVC (km/s)    58       59       60       61       62       63       64       65       PS Plot   
M6 Wolf 359 (Gl 406) 10 56 28.9 07 00 53 7.09 480 626 -22.56 D D D D D D D D P
M6 GJ 3828B 14 12 12.2 -00 35 17 13.09 2400 - -13.31
M6 GL 577BC 15 05 49.1 64 02 49 7.19 1200 91 -8.54 D D D D D D D P
M6 KPNO-Tau 3 04 26 29.4 26 24 14 13.32 4800 - -2.14
M6 V410 Anon 13 04 18 17.2 28 28 42 12.95 2400 - -3.17
M6 USco CTIO 66 16 01 49.6 -23 51 08 12.91 2400 41 -1.88 D D D D D D D D P
M6 DENIS 1605-24 16 05 14.0 -24 06 52 12.84 2400 39 -1.55 D D D D D D D D P
M6 2MASS 2234+40 22 34 41.6 40 41 39 12.57 2400 57 19.19 D D D D D D D D P
M6 S Ori 12 05 37 57.4 -02 38 45 14.23 6000 16 4.00 D D D D D D D D P
M6.5 SCH 1612-20 16 12 11.9 -20 47 27 13.66 4800 30 -1.19 D D D D D D D D P
M6.5 CFHT Tau-7 04 32 17.9 24 22 15 11.52 1200 52 -28.67 D D D D D D D D P
M6.5 2MASS J0423+28 04 23 06.1 28 01 20 12.24 2400 - -3.17
M7 p Oph GY 5 16 26 21.5 -24 26 01 12.57 2400 66 0.01 D D D D D D D P
M7 Usco CTIO 100 16 02 04.3 -20 50 43 12.84 2400 47 -2.59 D D D D D D D P
M7 MHO Tau-5 04 32 16.1 18 12 46 11.07 1200 - -2.72
M7 MHO Tau-4 04 31 24.0 18 00 22 11.65 1200 - -2.90
M7 LP 402-58 23 36 44.0 21 53 39 12.71 3600 62 -26.62 D D D D D D D D P
M7 AP 325 03 35 47.2 49 17 43 15.28 9600 - -5.43
M7 sOri 31 05 38 20.8 -02 46 13 15.19 10800 - 3.69
M7.5 p Oph GY 3 16 26 21.9 -24 44 40 12.34 2400 - -0.28
M7.5 USco CTIO 130 15 59 43.7 -20 14 40 14.20 3600 20 -3.27 D D D D D D D P
M8 DENIS 1619-24 16 19 29.9 -24 40 47 14.23 4800 20 -0.36 D D D D D D D P
M8 SCH 1623-23 16 23 51.6 -23 17 27 13.55 3600 30 27.76 D D D D D D D D P
M8 SCH 1622-19 16 22 43.8 -19 51 06 12.35 2400 59 27.78 D D D D D D D D P
M8 2MASS 1139-31 11 39 51.1 -31 59 21 12.69 3600 52 -19.05 D D D D D D D P
M8 2MASS 1207-39AB     12 07 33.4 -39 32 54 13.00 2400 35 -17.61 D D D D D D D D P
M8 2MASS J0422+19 04 22 13.3 19 34 39 12.86 2400 - -3.23
M8 AP 306 03 19 41.3 50 30 45 15.26 6000 - -5.17
M8 LP 412-31 03 20 59.6 18 54 23 11.74 2400 109 -11.61 D D D D D D D D P
M8.5 p Oph GY 310 16 27 38.6 -24 38 39 13.27 4800 - 0.00
M8.5 Gl 569Bab 14 54 29.4 16 06 09 10.61 2400 - 14.79
M9 2MASS 0140+27 01 40 02.6 27 01 50 12.49 2400 79 -18.48 D D D D D D D D P
M9 TWA 5B 11 31 55.4 -34 36 29 12.60 1200 46 -18.39 D D D D D D D P
M9 CFHT Tau-3 04 36 38.9 22 58 12 13.72 7200 - -1.37
M9 2MASS 0443+00 04 43 37.6 00 02 05 12.51 2400 - -2.24
M9.5 2MASS 0608-27 06 08 52.8 -27 53 58 13.60 4800 29 5.98 D D D D D D D D P
M9.5 KPNO Tau 4 04 27 28.0 26 12 05 15.00 8400 - -2.70
M9/L2 2MASS 2140+16 21 40 29.3 16 25 18 12.94 4800 - 25.89
L0 2MASS 0345+25 03 45 43.2 25 40 23 13.99 2400 25 -6.48 D D D D D D D D P
L0 LP 944-20 03 39 35.2 -35 25 45 10.73 1200 - -9.98
L0.5 2MASS 0746+20AB 07 46 42.6 20 00 32 11.74 1440 60 7.40 D D D D D D D P
L1 2MASSW J0208+25 02 08 18.3 25 42 53 14.02 7200 - -17.25
L1 2MASSW J1658+70 16 58 03.8 70 27 02 13.29 2400 - -3.38
L1.5 2MASSW J2057-02 20 57 54.1 -02 52 30 13.12 3600 - 26.74
L2 2MASSW J0015+35 00 15 44.8 35 16 03 13.82 7200 - -21.28
L2 G196-3B 10 04 20.7 50 23 00 14.83 2400 9 -23.57 D D D D D D D D P
L2 Kelu-1 13 05 40.2 -25 41 06 13.42 5400 20 -11.99 D D D D D D D D P
L2.5 2MASSW J2104-10 21 04 14.9 -10 37 37 13.85 4800 - 27.14
L3 2MASSW J1506+13 15 06 54.4 13 21 06 13.41 2400 - -11.82
L3.5 2MASS 0036+18 00 36 16.2 18 21 10 12.44 2400 72 -24.59 D D D D D D D D P
L4 GD 165B 14 24 39.1 09 17 10 15.55 5400 5 -9.39 D D D D D D D D P
L4.5 2MASSW J2224-01 22 24 43.8 -01 58 52 14.05 3600 - 29.31
L5 2MASS 1507-16 15 07 47.7 -16 27 39 12.82 2400 56 7.30 D D D D D D D D P
L7 DENIS 0205-11AB 02 05 29.4 -11 59 30 14.58 1200 8 4.62 D D D D D D D D P
T0 SDSS 0423-04 04 23 48.6 -04 14 04 14.45 2400 17 19.27 D D D D D D D D P
T0 SDSS 1520+35 15 20 39.7 35 46 21 15.54 8400 - 10.43
T1.5 SDSS 0909+65 09 09 00.7 65 25 27 16.03 8400 - -18.45
T2 SDSS 1254-01 12 54 53.9 -01 22 47 14.88 4200 17 -18.41 D D D D D D D D P
T2.5 2MASS 1106+27 11 06 11.3 27 54 23 14.82 7200 - -10.33
T2.5 SIMP 0136+09 01 36 56.6 09 33 47 13.46 4800 - -21.88
T4.5 2MASS 0559-14 05 59 19.1 -14 04 48 13.83 1200 22 22.54 D D D D D D D D P
T5 2MASS 2254+31 22 54 18.8 31 23 49 15.28 2400 - 21.24
T5 2MASS 1503+25 15 03 19.6 25 25 20 13.94 4800 - 13.12
T6p 2MASS 0937+29 09 37 34.7 29 31 42 14.65 3600 19 -28.64 D D D D D D D D P
All coordinates and J-band photometry are from the 2MASS All-Sky Data Release. The above data are published in McLean et al. (2007) and Rice et al. (2010).

Itime is the total integration time in seconds. The average SNR is the average per resolution element accross all reduced orders. BVC is the applied barycentric velocity correction in kilometers per second.

Notes: Objects missing order 60 lack arc lamp lines for wavelength calibration. Other orders are calibrated with OH night sky lines.
Grayed out objects have been reduced and are currently available by request only.

The NIRSPEC Brown Dwarf Spectroscopic Survey (BDSS)

Paper I: McLean, I.S., McGovern, M.R., Burgasser, A.J., Kirkpatrick, J.D., Prato, L., & Kim, S.S. 2003, ApJ, 596, 561

Paper II: McLean, I.S., Prato, L., McGovern, M.R., Burgasser, A.J., Kirkpatrick, J.D., Rice, E. L., & Kim, S.S. 2007, ApJ, 658, 1217

Additional Papers

High-Resolution: Rice, E.L., Barman, T., McLean, I.S., Prato, L., & Kirkpatrick, J.D. 2010, ApJS, 186, 63

Low-Resolution: McGovern, M.R., Kirkpatrick, J.D., McLean, I.S., Burgasser, A.J., Prato, L., & Lowrance, P.J. 2004, ApJ, 600, 1020

Low-Resolution: Kirkpatrick et al. 2010, arXiv:1008.3591v1

Please cite the appropriate above references if you use or display these data in your publications or presentations.



Created by Mark McGovern
Maintained by Gregory Mace and Emily Rice
Last Updated: 26 August 2010
E-mail: gmace {AT} astro {o} ucla {o} edu