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Constraining the total baryon number of the universe with XMM-Newton high resolution spectra
D a n i e l N i e to C a s ta Я o ESAC
XMM-Newton


Where are the missing baryons?

H o w o u r fr i e n d X M M - N e w to n c a n h e l p u s to fi n d th e m


Universe Composition


D ark E n erg y 70% D a r k M a tte r 25% O r d in a r y M a tte r 5%






Ordinary Matter


H a d r o n s ( s u f f e r e le c tr o w e a k a n d s tr o n g in te r a c tio n s )
­

Baryons (fermions)


Composed by three quarks Proton, neutron Composed by one quark and one antiquark Unstable

­

Mesons (bosons)




L e p to n s ( s u f f e r e le c tr o w e a k i n te r a c tio n )
­ ­

ЁLeptosЁ = light Electron, muon, tauon and neutrinos


Baryons appear in the past and hide in the present


H ig h R e d s h if t z : b a r y o n n u m b e r O K L o w R e d s h if t z : 4 5 % m is s in g


Cosmological Simulations


Cosmological Simulations


How can we detect WHIM?






Baryon Matter: Ionized Atoms ­ H-like ­ He-like High resolution soft X-ray absorption spectroscopy: ­ RGS (XMM-Newton) X-ray Transitions: ­ Candidate: O 2 1S -1s2p 1P ) O VII (1s 0 1 ­ 21.602 е O VIII (1s-2p) ­ 18.969 е


Reflecting Grating Spectrometer (RGS)


Two RGS on board XMM-Newton High resolution soft X-ray spectroscopy: ­ High resolving power (150 to 800) ­ Range from 5 to 35 е [0.33 to 2.5 keV] X-ray Transitions within the range: ­ Heavy elements L-shell ­ Light elements K-shell transitions He-like triplets






Bright Extragalactic Continuum Sources Candidates

·

Mkn 421 z = 0.03

·

Pks 2155-304 z = 0.117

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·


XMM-Newton RGS data


XMM-Newton RGS data


XMM-Newton RGS data

23

24


XMM-Newton RGS data


Conclusion


Next Steps


N o e v id e n c e o f f ila m e n ts f o r th e m o m en t

F o c u s in g in P k s 2 1 5 5 - 3 0 4 d a ta T a k in g a d v a n ta g e o f n e w S A S v e r s io n
­



Improved Rgsproc



D e v e lo p in g to o ls to m e r g e s p e c tr a f r o m d if f e r e n t o b s e r v a tio n s