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1,DR7 http://classic.sdss.org/dr7/access/index.html
2, DR5 光谱下载网页:
http://das.sdss.org/www/html/spectro/dr5index.html
DR2-6 下载页面:
http://das.sdss.org/www/html/das2.html
3,历次数据的不同
http://www.sdss.org/dr12/algorithms/spectrophotometry/
1,光谱没有做galactic extinction correction
since dr2 not corrected for foreground Galactic reddening
2,光谱标准星 F8 subdwarfs,similar in spectral type to the SDSS primary standard BD+17 4708.
edr&dr1:认为这8颗星的平均光谱与BD+17 4708的Pickles (1998)模型一样。
dr2&dr3:用的另外一个理论模型Kurucz model atmospheres (Kurucz 1992)
另外一个较小的改正是fiber星等:加入了3“的seeing以及fiber的overlapping源。
3,dr6 SEGUE (Sloan Extension for Galactic Understanding and Exploration)针对Milk Way的
dr6是sdss II 期的开始,其pipline与之前相比有变化。且开始了SEGUE
http://classic.sdss.org/dr6/start/aboutdr6.html
4,dr7
dr7的改进是针对SEGUE的。dr7 仍是sdss II 期的pipline
5,Dr8 用了新的pipline
https://www.sdss3.org/dr8/whatsnew.php
6,Updates in DR9, unchanged for DR10 through DR12
Data Release 13 is the latest public release of BOSS spectra. Data Release 9 was the first public release of BOSS spectra. Prior to that, Data Release 8 included all BOSS imaging.
4,cross_ID
SELECT s.plate, s.mjd, s.fiberid,s.fiberMag_u,s.fiberMag_g,s.fiberMag_r,s.fiberMag_i,s.fiberMag_z,s.petroMag_u,s.petroMag_g,s.petroMag_r,s.petroMag_i,s.petroMag_z,s.psfMag_u,s.psfMag_g,s.psfMag_r,s.psfMag_i,s.psfMag_z,s.z,s.ra,s.dec
FROM #upload u
JOIN SpecPhotoAll s ON (s.plate=u.up_plate AND s.mjd=u.up_mjd AND s.fiberID=u.up_fiber)
5,http://classic.sdss.org/dr7/dm/flatFiles/spPlate.html
SDSS 光谱fits的构成
http://www.astro.princeton.edu/PBOOK/spectro/spectro.htm
光谱构成
DR7
http://classic.sdss.org/dr7/products/spectra/read_spSpec.html
DR12
https://physics.stackexchange.com/questions/261384/sloan-digital-sky-survey-sdss-spec-file-headers
6 CasJob 做交叉(ra dec)
http://sdssdr8.lamost.org/casjobs/aqueries.aspx
SELECT
m.ra AS ra1, m.dec AS dec1,
n.objid, n.distance,
o.ra AS ra2, o.dec AS dec2 into mydb.MyTable_1 from mydb.SDSS_QSOs_05_RADEC AS m
CROSS APPLY dbo.fGetNearestObjEq( m.ra, m.dec, 0.5) AS n
JOIN PhotoObj AS o ON n.objid=o.objid
2
SELECT
m.ra AS ra1, m.dec AS dec1, n.distance,
o.ra AS ra2, o.dec AS dec2,o.petroMag_g AS Petro_g,o.petroMag_r AS Petro_r,o.petroMag_i AS Petro_i
FROM MyDB.Roma AS m
OUTER APPLY dbo.fGetNearestObjEq( m.ra, m.dec, 0.3) AS n
LEFT JOIN PhotoObj AS o ON n.objid=o.objid
(plate,mjd,fiber)
SELECT
m.plate AS plate1, m.mjd AS mjd1,m.fiber AS fiber1,
s.plate AS plate2,s.mjd AS mjd2,s.fiberID AS fiber2 into mydb.Mytest
from mydb.SDSS_QSOs_05_PMF AS m
JOIN SpecObjAll AS s ON (m.plate=s.plate AND m.mjd=s.mjd AND m.fiber=s.fiberID)
7 SDSS 转AB
mAB=mSDSS+[−0.036, 0.012, 0.010, 0.028, 0.040]
8,SDSS命名
SDSS天体都是按历元J2000.0时的位置命名,比如星系SDSS J0146-0929,坐标为赤经01:46:56.01,赤纬 -09:29:52.5
9,SDSS的光谱分辨率:
仪器的本征弥散速度:~60-79 km/s,对应的黑洞质量大约是10e6.3solar mass
9,SDSS magnitude and flux
首先,要知道AB星等的来源:
https://en.wikipedia.org/wiki/AB_magnitude
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其中,,3631Jy作为零点星等。
而在SDSS的星等系统中,用的是反双曲线函数星等asinh magnitude:
https://www.sdss.org/dr12/algorithms/magnitudes/#nmgy
其中的f/f0仍然是针对于3631Jy的,所以对于SDSS的星等转流量公式就是将上述公式翻转过来求f/f0,然后通过得出流量密度,单位是Jy。
另外,SDSS星等和AB星等有微小的差别,所以有改正量:
https://www.sdss.org/dr12/algorithms/fluxcal/#SDSStoAB
但对于SDSS星表中给出的flux并不是f/f0,而是10e-9的f/f0,即,其星等零点是3.631e-6,所以SDSS的星等和SDSS的流量公式是:
��
公式
中的f/f0 * 10e9 才是SDSS的流量(nanomaggies)。
10, SDSS和其它星等的转化。
https://www.sdss.org/dr12/algorithms/sdssubvritransform/
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