Bibcode
DOI
Trapero, J,; Beckman, J. E.; Serra-Ricart, .M.; Davies, Rodney D.; Watson, Robert A.; Garcia Lopez, R. J.
Referencia bibliográfica
The Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 445, no. 1, p. 231-239
Fecha de publicación:
5
1995
Revista
Número de citas
7
Número de citas referidas
6
Descripción
We first discovered the presence of a particularly massive cloud in the
neighborhood of the Sun, close to the Galactic plane in the direction of
Perseus, toward l = 150 deg, b = -10 deg, using interstellar absorption
by the 7699 A resonance line of K I (Trapero et al. 1992). In the
present investigation we show the results of mapping the cloud in the 21
cm line of H I, supplemented by further K I observations. This
combination is particularly effective, since the K I observations give
us distances, within close limits, and accurate velocities of the single
strong interstellar component detected along each line of sight, which
enables us to identify the cloud as seen in absorption in the H I
spectra, from among many emission components due to more distant clouds
in the plane. The absorption spectra in H I at 21 cm can then be used to
find temperatures and to carry out more comprehensive mapping than using
K I. We find that the cloud has kinetic temperatures going down to 30 K,
densitites in the range up to 70/cu cm, a diameter of approximately 15
pc, and a mass of some 1300 solar mass. The cloud is a good candidate to
contain a molecular core.