{"id":566,"date":"2017-10-11T00:00:01","date_gmt":"2017-10-11T00:00:01","guid":{"rendered":"http:\/\/pfs.ipmu.jp\/blog\/?p=566"},"modified":"2019-05-28T02:47:46","modified_gmt":"2019-05-28T02:47:46","slug":"meeting-on-data-analysis-software-in-princeton-%e3%83%87%e3%83%bc%e3%82%bf%e8%a7%a3%e6%9e%90%e3%82%bd%e3%83%95%e3%83%88%e4%bc%9a%e8%ad%b0%e3%81%8c%e3%83%97%e3%83%aa%e3%83%b3%e3%82%b9%e3%83%88","status":"publish","type":"post","link":"https:\/\/pfs.naoj.org\/blog\/2017\/10\/p566","title":{"rendered":"Meeting on data analysis software in Princeton"},"content":{"rendered":"

Written by\u00a0 Naoki Yasuda (Kavli IPMU)<\/em><\/p>\n

The galaxies PFS will observe are more than 8 billion\u00a0light years away and their brightness is less than\u00a0one to a 10 million of the stars visible to naked eyes.\u00a0To measure the properties of these faint galaxies\u00a0accurately, we have to develop data analysis software\u00a0which can deal with various kinds of noises included in the acquired data.<\/p>\n

From 20th to 22nd September 2017, researchers who\u00a0will develop 2D data reduction pipeline have gathered\u00a0at Princeton University, New Jersey, USA. Researchers\u00a0coming from Princeton University, National Astronomical\u00a0Observatory of Japan, and Kavli IPMU have discussed the
\nitems to develop and roles of each person. Here “2D” data\u00a0reduction means the processing to extract 1 dimensional\u00a0spectra from the 2 dimensional images of detectors which\u00a0record the output of 2394 fibers. After it, “1D” data\u00a0reduction will follow to measure redshifts of galaxies and intensity of emission\/absorption lines etc..<\/p>\n

Within PFS, the light from each object will be directed\u00a0to spectrograph through different fibers and the spectra\u00a0will be recorded side by side on the detectors. The separation\u00a0of the adjacent spectra is a bit small to maximize the number of\u00a0objects to be observed and the spectra will overlap with each other. These spectra should be optimally\u00a0separated. The characteristics of the fibers are slightly different\u00a0and these effect also should be taken into account. Needless\u00a0to say, both wavelength and flux should be calibrated precisely.<\/p>\n

\"\"<\/a>
\n(Spectra taken at the laboratory. Since one 2D image has about 600 spectra, their separation is a bit small.)<\/em><\/p>\n

In addition to these, the sky is 1000 times brighter than\u00a0the objects we are planning to observe, even at the summit of Mt. Mauna Kea\u00a0where Subaru telescope is placed (~4200 m high). This is caused by\u00a0the OH air-glow. The emission lines by OH molecule is though to be observed\u00a0at the specific wavelengths, so we have to remove the sky OH emission lines cleanly from\u00a0the observed spectra.<\/p>\n

In the meeting, we have listed up and confirmed these challenges\u00a0we will face and decided to start development using simulated images assuming the observational conditions. We will prepare for the real observing data which will be\u00a0delivered in 2019 at the engineering run.<\/p>\n","protected":false},"excerpt":{"rendered":"

Written by\u00a0 Naoki Yasuda (Kavli IPMU) The galaxies PFS will observe are more than 8 billion\u00a0light years away and their brightness is less than\u00a0one to a 10 million of the stars visible to naked eyes.\u00a0To measure the properties of these faint galaxies\u00a0accurately, we have to develop data analysis software\u00a0which can deal with various kinds of noises included in the acquired… Read more »<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_locale":"en_US","_original_post":"566","footnotes":""},"categories":[2],"tags":[25,15],"class_list":["post-566","post","type-post","status-publish","format-standard","hentry","category-development","tag-data-reduction","tag-software","en-US"],"_links":{"self":[{"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/posts\/566","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/comments?post=566"}],"version-history":[{"count":7,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/posts\/566\/revisions"}],"predecessor-version":[{"id":1274,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/posts\/566\/revisions\/1274"}],"wp:attachment":[{"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/media?parent=566"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/categories?post=566"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pfs.naoj.org\/blog\/wp-json\/wp\/v2\/tags?post=566"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}