Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Digital Low Dispersion Spectral Library Covering the 3500-7500AA
  Region Using the SAAO Radcliffe 1.9m Telescope's Cassegrain Spectrograph   We have created a digital spectral library, using low resolution optical
spectra, of photometric and spectral standard stars. The data were acquired
using the Cassegrain Spectrograph installed on the 1.9m Radcliffe telescope at
the South African Astronomical Observatory. The library consists of optical
wavelength (~ 3500-7500AA) spectra for main sequence and giant stars
encompassing those most commonly observed in the Galaxy, namely the late-B, A-,
F-, G-, K-, and early- to mid-M stars. We intend that our standard star spectra
will be especially useful for spectral classification of stars in the field and
Galactic clusters alike, and will have high pedagogic value when included into
representative Introductory Astronomy or Stellar Astronomy curricula for
undergraduate astronomy major and minor programs.
  We exploit the spectral library in order to derive spectral types for
seventy-six optically and X-ray selected members of the young open cluster NGC
6475. Comparison of spectral-type, optical and infrared photometric data to
theoretical colors derived from spectral type show that the reddening of the
cluster is E(B-V) = 0.068 +/- 0.012 (1sigma=0.058), a vector consistent with
earlier surveys. Our analysis also highlights the utility of such spectra in
rejecting cluster non-members, thereby allowing the creation of a clean sample
of bona fide cluster members for follow-up science observations.

37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph