Green Bank Galactic HI Partial-Sky Drift Scan Survey

1
First Science Results From
Green Bank Galactic HI Partial-Sky Drift Scan
Survey (GBGHIPSDSS)
Antonio Portas Kevin Blagrave Daniela
Goncalves Jason Boyles
Loren Anderson Crystal Anderson Bo Zhang
Jana Greenrich Dana Whitlow Monica Rodriguez
Ronald Maddalena Frank Ghigo Steven Gibson
2
Goals 1) Determine the properties of HI in our
Galaxy. 2) Serendipitously detect OH maser and
recombination lines.
Parameters Frequency switched by 3 MHz 4
windows 1) 1420 MHz (HI recomb. line at 1424
MHz) 2) 1667 MHz (OH masers at 1667 and 1665
MHz) 3) 1612 MHz (OH maser) 4) 1720 MHz (OH
maser recomb. line at 1715 MHz) 12.5 MHz
bandpass with 8000 channels per window -gt
0.3 km/s resolution 5 minute scans read out
every 10 seconds -gt 3000 spectra 9' beam
3
Sky Coverage
Bonn 408 MHz Continuum Survey
4
Sky Coverage
IRAS 100 um
5
Galactic recombination lines

• HI 156 _at_ 1.715 GHz
• too much RFI
• HI 166 _at_ 1.45 GHz
• rms noise about 0.4 K expected line at
  0.2 K

6
Galactic dynamic HI mass
VROT Vdop 220 Km s-1 sin (long) MHI V2ROT
R/G R 1.42 Kpc
7
(No Transcript)
8
OH Maser Super-Detection

Oblasti W3(OH) 8.9GHz (16.2.2002, National
Radio Astronomy Observatory, Green Bank, West
Virginia). Credit NRAO/GBT
9
1667MHz
Frequency vs. Scan number
10
RMS 0.005K
8 sigma detection
11
Surveys

• DSS
• IRAS 12 micron, 100 micron
• NVSS
• Bonn 408MHz
• H-alpha
• CO
• OH

12
1612MHz
Frequency vs. Scan number