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J/ApJ/722/367      HI clouds in Quadrant I of the Milky Way    (Ford+, 2010)

Milky Way disk-halo transition in H I: properties of the cloud population. Ford H.A., Lockman F.J., McClure-Griffiths N.M. <Astrophys. J., 722, 367-379 (2010)> =2010ApJ...722..367F
ADC_Keywords: H I data ; Milky Way ; Interstellar medium ; Radio lines ; Surveys ; Molecular clouds Keywords: galaxies: structure - Galaxy: halo - ISM: clouds - ISM: structure - radio lines: ISM Abstract: Using 21cm HI observations from the Parkes Radio Telescope's Galactic All-Sky Survey, we measure 255 HI clouds in the lower Galactic halo that are located near the tangent points at 16.9≤l≤35.3° and |b|≲20°. The clouds have a median mass of 700M and a median distance from the Galactic plane of 660pc. Description: The data used in this paper are from the Galactic All-Sky Survey (GASS), an HI survey of the entire southern sky to declination δ≤1° made with the Parkes Radio Telescope (McClure-Griffiths et al. 2009ApJS..181..398M). GASS is fully sampled at an angular resolution of 16', covers -400km/s≤VLSR≤+500km/s at a channel spacing of 0.8km/s, and has an rms noise per channel of ΔTb∼60mK. The data analyzed here are from the first release of the survey which has not been corrected for stray radiation. A total of 255 disk-halo HI clouds, some >2kpc from the plane, were detected at the tangent points in the first quadrant region of GASS data, a region in longitude, latitude, and velocity that is symmetric to the fourth quadrant region studied in Paper I (Cat. J/ApJ/688/290). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 61 255 Observed properties of tangent point HI clouds in the Quadrant I region table2.dat 76 255 Derived properties of tangent point HI clouds in the Quadrant I region
See also: VIII/73 : HI Parkes All Sky Survey Catalogue (HIPASS) (Meyer+, 2004) J/ApJ/702/1472 : Column densities for HI, AlIII, SiIV, CIV, OVI (Savage+, 2009) J/ApJ/688/290 : GASS HI survey of the lower halo (Ford+, 2008) J/ApJ/626/887 : HI clouds in Southern Galactic Plane Survey (Kavars+, 2005) J/AJ/122/3155 : Peculiar HI cloud near galactic plane (Higgs+, 2001) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 5 F5.2 deg GLON Galactic longitude 7- 12 F6.2 deg GLAT Galactic latitude 14- 18 F5.1 km/s VLSR Local Standard of Rest velocity 20- 23 F4.1 km/s e_VLSR Uncertainty in VLSR 25- 28 F4.2 K Tpk Peak brightness temperature (uncertainties are 0.07K) 30- 33 F4.1 km/s DelV FWHM of velocity profile ΔV 35- 38 F4.1 km/s e_DelV Uncertainty in DelV 40- 44 F5.2 10+19cm-2 NHI HI column density peak 46- 49 F4.2 10+19cm-2 e_NHI Uncertainty in NHI 51- 52 I2 arcmin bmin Angular extent minor axis (1) 54- 55 I2 arcmin bmaj Angular extent major axis (1) 57- 61 F5.1 Msun/kpc2 MHI/D2 HI surface density (mass divided by squared distance) (2)
Note (1): Uncertainties in the maximum angular extents are dominated by background levels surrounding the cloud and are assumed to be 25% of the estimated values. Note (2): Mass uncertainties are dominated by the interactive process used in mass determination and are assumed to be 40% of the estimated values.
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 5 F5.2 deg GLON Galactic longitude 7- 12 F6.2 deg GLAT Galactic latitude 14- 18 F5.1 km/s VLSR Local Standard of Rest velocity 20- 23 F4.1 km/s e_VLSR Uncertainty in VLSR 25- 28 F4.1 km/s Vdev Deviation velocity 30- 33 F4.1 km/s e_Vdev Uncertainty in Vdev 35- 37 F3.1 kpc Dist Heliocentric distance 39- 41 F3.1 kpc e_Dist Uncertainy in Dist 43- 45 F3.1 kpc R Galactocentric radius 47- 49 F3.1 kpc E_R Upper limit uncertainty in R (1) 51- 55 F5.2 kpc Z Height from the Galactic plane 57- 60 F4.2 kpc e_Z Uncertainty in Z 62- 63 I2 pc Rad Radius of HI cloud 65- 66 I2 pc e_Rad Uncertainty in Rad 68- 71 I4 Msun MHI Physical HI mass 73- 76 I4 Msun e_MHI Uncertainty in MHI
Note (1): Along a given line of sight, the smallest Galactocentric radius possible is at the tangent point. If the cloud is not located at the tangent point it must be farther away from the center and the error on R must be positive.
History: From electronic version of the journal References: Ford et al. Paper I. 2008ApJ...688..290F Cat. J/ApJ/688/290
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 10-Jul-2012
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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