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    Active Region Moss: Doppler Shifts from Hinode/EIS
    (2012-05-05) Tripathi, Durgesh; Mason, Helen E.; Klimchuk, James A.
    Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the ac- tive regions. In this paper we have used an active region observation recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) onboard Hinode on 12-Dec- 2007 to measure the Doppler shifts in the moss regions. We have distinguished the moss regions from the rest of the active region by de ning a low density cut-o as derived by Tripathi et al. (2010). We have carried out a very careful analy- sis of the EIS wavelength calibration based on the method described in Young, O'Dwyer and Mason (2012). For spectral lines having maximum sensitivity be- tween log T = 5:85 and log T = 6:25 K, we nd that the velocity distribution peaks at around 0 km s􀀀1 with an estimated error of 4􀀀5 km s􀀀1. The width of the distribution decreases with temperature. The mean of the distribution shows a blue shift which increases with increasing temperature and the distribution also shows asymmetries towards blue-shift. Comparing these results with observables predicted from di erent coronal heating models, we nd that these results are consistent with both steady and impulsive heating scenarios. However, the fact that there are a signi cant number of pixels showing velocity amplitudes that exceed the uncertainty of 5 km s􀀀1 is suggestive of impulsive heating. Clearly, further observational constraints are needed to distinguish between these two heating scenarios.
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    Ten things you may not know about the Higgs boson
    (Hindu group of publacation, 2012-07-14)
    Peter higgs' best-known paper on the new particle was initially rejected. The hihggs mechanism explains only a small fraction of the mass in the universe
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    The Higgs hunt
    (Hindu group of publication, 2012-07-14) RAMACHANDRAN, R.
    CERN announces that the highly elusive Higgs boson had in all probability been discovered
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    Beyond standard model
    (Hindu group of publication, 2012-07-27) Tarun, Sauradeep
    The detection of higgs complete the experimental chapter of verifying the standard model of particle physics
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    Mirror to space
    (Hindu Group of Publication, 2011-02-26) Bandyopadhay, Amalendu
    In the 20 years of its functioning, the Hubble Space Telescope has revealed hitherto unknown secrets.
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    Mercury up close
    (Hindu Group of Publication, 2011-06-04) Bandyopadhay, Amalendu
    When MESSENGER, launched by NASA, began orbiting Mercury on March 18, it became the first spacecraft to do so.
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    Gentle giant
    (Hindu Group of Publication, 2011-04-23) Ramchandran, R.
    John Willard Milnor, the wizard of higher dimensions, gets the Abel Prize, which is regarded as the “Mathematician's Nobel”.
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    For a true picture
    (Hindu Group of Publication, 2011-11-04) Ramchandran, R.
    The use of Adaptive Optics and Robo-AO will go a long way in improving the performance of optical instruments such as telescopes.
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    Cosmic link
    (Hindu Group of Publication, 2011-03-12) Ramchandran, R.
    Scientists argue that cloud formation modulated by galactic cosmic rays has an impact on climate change.
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    Cosmic crash
    (Hindu Group of Publication, 2011-07-02) Ramchandran, R.
    Evidence of a gamma-ray burst picked up by a NASA spacecraft has scientists wondering what mighty cosmic event could have caused it.