Transcript HIPark – a parked Parkes survey

the faint end ….
…. in neutral gas
“luminous”
Radio spectroscopy
Upper limits to
space density of
intergalactic
HI Clouds
# Clouds
/Mpc3
/decade
MHI
Volume for each
survey that was
sensitive to MHI
Volume (Mpc3)
-
-
-
-
-
MHI
Upper limits to
space density of
intergalactic
HI Clouds
# Clouds
/Mpc3
/decade
HI in
Galaxies
MHI
Upper limits to
space density of
intergalactic
HI Clouds
# Clouds
/Mpc3
/decade
MHI
Lo & Sargent (1979)
MHI /L
Log MHI
Mpg
M81, CVn, NGC 1023 Groups
18
0.4
15
3
0.4
1.3
6.8
6.6
7.9
7.8
7.7
8.1
-8.7 -12.3 -11.5 -13.1 -15.2 –15.5
… the writing is on the wall…
(… and in the literature…)
more HI in M96
than the Ring
(Schneider etal 1989)
Giovanelli, Haynes, Chengalur
“Virgo HI Cloud”
HI Mass Function: (dashed curve)
Felton 1985, Luminosity
Function
F-T for MHI/L(L)
HI Content according to
galaxy mass
Integral HI mass content:
(1990)
7.0x107 Mo Mpc-3
(HIMF faint end slope:
a = -1.28 )
Parkes HIPASS results (2003):
Integral HI mass content:
6.1x107 Mo Mpc-3
( faint end slope:
a = -1.3 )
… what else in the meanwhile…
Relation of Galactic High Velocity Clouds to IGM…
… HVCs mostly within 200 kpc (Zwaan 2000, thesis)
HIPark – a parked Parkes survey
Goals:
ultra sensitive to low column densities
diffuse clouds in LG
… optically ?thin at the Lyman limit
How sensitive
& Milky Way halo
exercise in observational techniques
… rfi, passband calibration, …
good match to long maintenance periods
HI Park proposers…
•
•
•
•
Briggs
Barnes
de Blok
Freeman
•
•
•
•
•
Gibson
Korbalski
Reynolds
Staveley-Smith
Zwaan
Progess:
25 days observations – John Reynolds
extragalactic preview – Jackie Cooper
MOTIVE ?
QSO absorption line interception cross sections
DLA
Z=3
Ly break galaxy
CIV
MgII/ Lyman limit
(CII, FeII, SiII, …)
HI Column density distribution function
Petijean etal 1993
-10
Number of interceptions
in range: N to N+dN
f(N) dN
-15
Log f(NHI)
tLL > 1
Lya forest
IGM
-20
12
14
/unit Z
DLA
CIV
Log NHI
18
20
22
HI Map of M81 Group
Yun, Ho & Lo 1994
M82
M81
NGC 3077
NGC
3344
HIPARK Goal…
Sensitivity:
to achieve 6s < 3 x 1017 cm-2
need ~ 6 hours of integration per beam
Drift scan:
15’ beam transits in ~ 1 minute
a
~360 transits
Multibeam !!!
Barnes et al
Feed orientation for drift scans
1x
4x
3x
Path of
Survey
Strip:
Galactic
Coords
Dcloud >1 kpc
Limits
at 250on
kpc
tiny masses
…intoSculptor…
fill beam
3x104 dMpc2
solar masses
05:56
FORNAX
Dec –32d53’
R.A.
2200 km/s
0
03:34
22:55
Dec –32d53’
R.A.
2200 km/s
0
20:36
Sculptor
(Putman et al)
01:14
SCULPTOR
Dec –32d53’
R.A.
2200 km/s
0
22:55
Magellanic
Stream
(Putman et al)
DEEP
Centaurus
Survey
(Disney et al)
01:14
Dec –32d53’
R.A.
2200 km/s
0
22:55
Conclusions:
(no I.G. HI clouds…)
Large mass halos
Star Formation
Galaxies
Early Low mass halos
Star Formation
ISM Lost
Late Low mass halos
never capture gas,
(No Star
Formation)
No Intergalactic Neutral Hydrogen Clouds at Z=0
… faint end still not known… ATA… SKA
Sun up !
Velocity
1100
0
-500
RA
Velocity
1100
0
-500
RA
2800
Velocity
One Day – One Beam
0
-500
Right Ascension
1100
km/s
Velocity
Galactic Plane crossing: L ~ 250o
0
-500
RA
Velocity
1100
0
-500
RA
Velocity
1100
0
-500
RA