Analysis Work Space

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Peggy's version

WISE data in the public release for BRC 27 and additional WISE data to be released in March 2012 for BRC 34 and 38 will be the main focus of our research. We will augment this with data from the Spitzer archival data from the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS), Two-Micron All-Sky Survey (2MASS), the Midcourse Space Experiment(MSX), AKARI (literally "light" in Japanese, also known as Astro-F), and we will include IPHAS data for BRC 34 and 38 (IPHAS data will be added for BRC 27 if available in 2012). We will re-reduce and use serendipitous data available in only 2 Spitzer bands around Spitzer footprint areas previously studied, and we will re-reduce Spitzer data for BRC 38 if necessary. We will also obtain new ground based optical photometry in the Sloan bands i and r using the 2-m Las Cumbres Observatory Global Telescope (LCOGT) on Haleakala.

We will use newly released WISE catalog data to investigate point sources, performing manual photometric spot checks to assure validity of the data. We will perfrom photometry for Spitzer areas that are outside of existing analyzed Spitzer data. New photometry will be obtained using MOPEX (Makovoz & Marleau 2005) and the Aperature Photometry Tool (APT) (Laher et al 2012). Ground based data will flush out data set on the shorter wavelength end and help us identify star producing galaxies masquerading as YSOs.

Combining newly obtained data with all existing data and what is known in the literature, we will use infrared excess to look for candidate Young Stellar Objects (YSO) and to describe the properties of known YSO. We will use a method similar to Gutermuth and Koenig color selection method to winnow down YSO candidates exhibiting infrared excess. Photometry data will be collected in spreadsheet form where we perform necessary calculations, such as flux density/magnitude conversions, and produce color-color and colormagnitude diagrams as well as spectral energy diagrams (SEDs).

To classify our sources, we will use the Koenig et al adaptation (2012 ApJ, 744, 130) for WISE data of the Gutermuth et al (2008, 2009). Using this method we will examine color-color diagrams, color magnitude diagrams and spectral energy diagrams to allow us to cut non YSO candidates. First we will remove objects outside our galaxy such as external galaxies with elevated star forming regions and active galacitic nuclei (AGN). Next we will removed shock emmision blobs and resolved structures based on established color restraints. We will then identify YSOs candidates by their class using color criteria.

Luisa's edited version:

as many changes as i made, i still think what you did is REALLY close. i added full references here to things that i wasn't sure you had yet in your own reference list; they should appear in the final version as just Lname et al. (20xx) with the full reference listed in a 'references' section at the end. Please let me know if this all makes sense, or if i did something funny -- i've got a preschooler dancing around me at the moment.


The main focus of our analysis will be ~10-15 arcminute diameter regions around our three targets (BRC 27, 34, and 38). We will use infrared excesses to look for candidate Young Stellar Objects (YSOs) and to describe the properties of known YSOs in these regions. We will use WISE (Widefield Infrared Survey Explorer) data; the region around BRC 27 is already in the public release, but we will obtain data for all 3 of our regions from the upcoming WISE data release in March 2012. We will use the WISE catalogs and the WISE color selection mechanism from Koenig et al (2011), which is based on the Gutermuth (2008, 2009) Spitzer color selection, to select YSO candidates. These color cuts allow us to remove from consideration objects outside our galaxy such as external galaxies with elevated star forming rates and active galacitic nuclei (AGN), shock emmsion blobs, and resolved structures based on established color restraints. We will then assemble data for our YSO candidates from as many other archival sources as possible, including the literature, investigate the images of each candidate, and perform additional photometry as needed.

Data we already plan to include are from the Two-Micron All-Sky Survey (2MASS), the Midcourse Space Experiment(MSX), AKARI (literally "light" in Japanese, also known as Astro-F). Some Isaac Newton Telescope (INT) Photometric H-Alpha Survey (IPHAS) data for BRC 34 and 38 were reported in Barentsen et al. (2011, MNRAS, 415, 103); if the predicted IPHAS release happens in 2012, we will incorporate IPHAS data for our regions where possible. Additionally, there are ~5 arcminute 4-band Infrared Array Camera (IRAC) pointings in each of these regions obtained with Spitzer. The regions of IRAC 4-band coverage were analyzed for BRC 27 and 34 by a prior NITARP team (Johnson et al., 2012, Rebull et al. in prep; see also Choudhury et al. 2010 for BRC 27) and for BRC 38 by Choudhury et al. (2010) and Chauhan et al. (2009) ?? **I THOUGHT THERE WAS ANOTHER SPITZER ANALYSIS IN BRC 38 - PLEASE CHECK AND ADD CITATION IF IT EXISTS ** I THINK THIS IS IT - P2**. For each of these 4-band regions, there are serendipitously obtained "flanking fields" of 2-band coverage with IRAC. We will use these serendipitously obtained data to aid in our assessment of YSO candidates. We will also include any Multiband Imaging Photometer for Spitzer (MIPS) data, as appropriate. The Spitzer data may require us to re-reduce or at least redo the photometry for our targets of interest.

Through Co-I J. D. Armstrong, we will also obtain new ground based optical photometry in the Sloan bands i and r using the 2-m Las Cumbres Observatory Global Telescope (LCOGT) on Haleakala. Ground based data will flush out data set on the shorter wavelength end and help us identify star producing galaxies masquerading as YSOs. These data will need to be reduced and photometry performed on all relevant sources.

If a rereduction of the Spitzer data is needed, we will use MOPEX (Makovoz & Marleau 2005) to construct the mosaics. For both the Spitzer and new optical data, we will obtain photometry using the Aperature Photometry Tool (APT) (Laher et al 2012).

We will collect all the photometry data in Excel spreadsheet form, where we can perform necessary calculations, such as flux density/magnitude conversions, and produce color-color and color-magnitude diagrams as well as spectral energy distributions (SEDs). We will use the shape of the objects in all available images, their colors and locations in color-magnitude and color-color diagrams, their projected location in space, and the shape of their SEDs to assess individual YSO candidates, following the procedure in, e.g., Johnson et al. (2012 -- a 2011 NITARP team), Rebull et al. 2011 -- a 2010 NITARP team), and Guieu et al. (2009, ApJ, 720, 46 -- a 2005-2007 NITARP team)