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The Lambda Orionis Star Forming Region. a Study in X- Rays

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The Lambda Orionis Star Forming Region. a Study in X- Rays TThhee LLaammbbddaa OOrriioonniiss SSttaarr FFoorrmmiinngg RReeggiioonn.. AA ssttuuddyy iinn XX-- RRaayyss Trainee: Francisco J. Galindo Guil Universidad Autónoma de Madrid (UAM) Tutor: David Barrado y Navascués Laboratorio de Astrofísica Espacial y Física Fundamental (LAEFF-INTA) (ESAC), Madrid Introduction • •Lambda Orionis belongs to the Orion B30 constellation. •Around Lambda Orionis there is a Star Forming Region. B35 Objective C69 LDN1588 •Identify with X-Rays (XMM data) very low mass members from LOSFR and derive the Initial Mass IRAS 100 microns Function, IMF. LDN1603 The Lambda Orionis Star Forming Region: star formation triggered by a SN? IRAS 100 micron, 10x10 deg Barnard 30 4.5 deg Collinder 69, 6 Myr Barnard 35 Barnad 30, 3 Myr Barnard 35, 3 Myr LDN1603, 1 Myr Doland & Mathieu (2002) Collinder 69 LDN1588, 1Myr LDN1588 LDN1603 Lambda Orionis: a multiwavelength approach The cluster has been studied already in others Dolan & Mathieu wavelengths. (1999, 2001, 2002) Stars -Optical.- vbyRIZ -Near IR.- JHK ByN et al. 2004 -Mid-IR.- Spitzer 3.6 - 24 microns -Optical and near-IR spectroscopy 0.072 BD 0.015 IPMO CFHT + 12K Mosaic Barrado y Navascués et al. 2004, 2005 Why X-Ray Data? 1.X-Rays information is essential. 2.The interest in a multiwavelengths study includes X-rays. 3. Verify the universality of the IMF 1. Information from X-ray •Very low-mass members can be detected in X-Rays (not affected by strong extinction). •Study of magnetic activity of already confirmed members. •Study the evolution of the X-Ray Luminosity Functions. ~600 Myr ~100 Myr David Barrado y Navascués BUSCA, optical Spectral energy 2. The interest in a multiwavelength data distribution Stromgren v Ic X-ray Omega2000, IR Spitzer 3.6-24, mid-IR 3. Study the universality of IMF •Fit the IMF for the stars of LOSFR. •The study of a XMM data must improve the IMF. •Now our faintest candidate cluster member ~0.015 Solar mass. David Barrado y Navascués X-Ray data and XMM •Study some regions with XMM. •There's 6 observations of 28000 s each. •Measures with all the instruments: RGS1, RGS2, MOS1, MOS2, pn, OM. B30 B35 C69 LDN1588 LDN1603 David Barrado y Navascués Using SAS •Data reduction: SAS. !Reduce the data with the standard tasks. First re sults: Barnard30 Continue with the Next steps: identification of the stars in the different regions. XMM-Newton image overlapped onto a Spitzer/MIPS at 24 micron Derive the IMF.
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