“HI巡天”的版本间差异

2021年3月24日 (三) 08:11的版本

The HI Parkes All-Sky Survey (HIPASS) covered 30000 deg2 and produced a final catalog of around 5000 HI detections with a median redshift of 2800 km/s.

Arecibo Legacy Fast ALFA Survey (ALFALFA) will map 7000 deg2 and is expected to detect more than 25,000 extragalactic HI line sources out to redshifts of 18,000 km/s.

Arecibo Galaxy Environment Survey (AGES), will cover a total area of 200 deg2 (divided into 13 predesignated regions to sample different environments) to greater depth

The H I Nearby Galaxy Survey (THINGS)," a high spectral (≤5.2 km s–1) and spatial (~6) resolution survey of H I emission in 34 nearby galaxies obtained using the NRAO Very Large Array (VLA).
public data [3]

Nançay Interstellar Baryons Legacy Extragalactic Survey (NanCay Radio Telescop 100m)

Must have both SDSS magnitudes and optical spectrum;
Must lie within the local volume (900<cz<12,000 km s−1);
Uniform sampling of each 0.5 magnitude wide bin in absolute z-band magnitude, Mz;
Preferentially observe nearby objects;
No a priori selection on color.

这种on source的观测比ALFALFA这种盲测的好更高信噪比，但是还是有一些星系用了Arecibo做了follow up的定点观测，灵敏度更高，可以到mJy以下，(可以探测Lr < 10^8.5的蓝星系)。参见[4]

@@ 第5行： / 第5行： @@
 ===ALFALFA===
-*Arecibo Legacy Fast ALFA Survey (ALFALFA) will map 7000 deg2 and is expected to detect more than 25,000 extragalactic HI
+*Arecibo Legacy Fast ALFA Survey (ALFALFA) will map 7000 deg2 and is expected to detect more than 25,000 extragalactic HI line sources out to redshifts of 18,000 km/s.
+:*the spatial resolution of the grid to 4.3'x3.8'
-line sources out to redshifts of 18,000 km/s.
+:*spectral velocity resolution is 11 km/s after smoothing is applied,
 * Catalog [https://arxiv.org/abs/2011.02588]
 * data webpage [http://egg.astro.cornell.edu/alfalfa/data/index.php]