Comments on: Another Higgs bump? Not so fast… http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/ Random samplings from a universe of ideas. Fri, 21 Nov 2008 22:06:41 +0000 http://wordpress.org/?v=2.3.1 By: mollishka http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25868 mollishka Sun, 13 May 2007 15:38:48 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25868 What's this about a 5-sigma resonance at 180GeV from this past week ... ? What’s this about a 5-sigma resonance at 180GeV from this past week … ?

]]> By: Borborigmi di un fisico renitente » Ancora tracce del bosone di Higgs? Il sottile confine tra le chiacchiere da bar e la dichiarazione pubblica http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25864 Borborigmi di un fisico renitente » Ancora tracce del bosone di Higgs? Il sottile confine tra le chiacchiere da bar e la dichiarazione pubblica Sun, 11 Mar 2007 23:21:38 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25864 [...] Tommaso (Dorigo) fa qualche alluzione un po’ azzardata: se nei dati di Conway ci fosse veramente il bosone di Higgs, allora dovrebbe fare capolino anche da altre parti, per esempio nello spettro di massa delle coppie di quark b, e lui quasi quasi suggerisce che in effetti sembrerebbe esserci. La discussione va avanti, John (Conway) fa due conti semplici semplici che smentiscono Tommaso e mostrano come nello spettro delle coppie di b non ci sia traccia di alcuna particella a 160 GeV, e via così. Tutto lecito e pure bello, peccato che, siccome queste chiacchiere viaggiano in chiaro sulla rete, qualche giornalista un po’ avido di scoop le intercetta, fa un paio di telefonate, equivoca più o meno di proposito due o tre cose, ed ecco che escono prima un articolo su New Scientist, e poi persino sul numero dell’Economist che ho tolto dal cellophane ieri. Risultato: smentite a destra e manca, disclaimer vari, e qualcuno di CDF si arrabbia pure. Accidenti. [...] […] Tommaso (Dorigo) fa qualche alluzione un po’ azzardata: se nei dati di Conway ci fosse veramente il bosone di Higgs, allora dovrebbe fare capolino anche da altre parti, per esempio nello spettro di massa delle coppie di quark b, e lui quasi quasi suggerisce che in effetti sembrerebbe esserci. La discussione va avanti, John (Conway) fa due conti semplici semplici che smentiscono Tommaso e mostrano come nello spettro delle coppie di b non ci sia traccia di alcuna particella a 160 GeV, e via così. Tutto lecito e pure bello, peccato che, siccome queste chiacchiere viaggiano in chiaro sulla rete, qualche giornalista un po’ avido di scoop le intercetta, fa un paio di telefonate, equivoca più o meno di proposito due o tre cose, ed ecco che escono prima un articolo su New Scientist, e poi persino sul numero dell’Economist che ho tolto dal cellophane ieri. Risultato: smentite a destra e manca, disclaimer vari, e qualcuno di CDF si arrabbia pure. Accidenti. […]

]]> By: Bump Hunting (Part 3??) | Cosmic Variance http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25867 Bump Hunting (Part 3??) | Cosmic Variance Fri, 09 Mar 2007 16:49:02 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25867 [...] CDF has seen a beautiful (no pun intended) signal for Z -> bb, and in that mass spectrum they could in principle see the Higgs but in my opinion it seems like they aren’t quite as sensitive as the tau pair analysis, and would not have been expected to see anything yet. [...] […] CDF has seen a beautiful (no pun intended) signal for Z -> bb, and in that mass spectrum they could in principle see the Higgs but in my opinion it seems like they aren’t quite as sensitive as the tau pair analysis, and would not have been expected to see anything yet. […]

]]> By: Rumors about the Higgs « A Quantum Diaries Survivor http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25865 Rumors about the Higgs « A Quantum Diaries Survivor Sat, 03 Mar 2007 23:28:49 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25865 [...] Now John  does a nice back-of-the-envelope calculation , showing that if the H->tau tau signal is real, there should be a more evident bump in the CDF Z->bb signal plot. And then I counter in the comments section of his post, arguing that indeed, my plot does not rule out a signal the size he sees in his tau-tau analysis. [...] […] Now John  does a nice back-of-the-envelope calculation , showing that if the H->tau tau signal is real, there should be a more evident bump in the CDF Z->bb signal plot. And then I counter in the comments section of his post, arguing that indeed, my plot does not rule out a signal the size he sees in his tau-tau analysis. […]

]]> By: tommaso dorigo http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25866 tommaso dorigo Sat, 03 Mar 2007 23:03:51 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/03/02/another-higgs-bump-not-so-fast/#comment-25866 Hi John, it's nice to meet virtually here to discuss your signal and my non-signal :) You did a clear back-of-the-envelope calculation, and I have little to object to it. Of course, one could try to make it a bit more precise (say, the efficiency at 160 GeV is larger than at 90, blah). The bottomline, though, I think is the one you already drew. Indeed, one should see a signal a tenth of the Z->bb or so in our plot. The signal would have a width of 20 GeV or so, though, that is almost twice as large as the Z peak, because our resolution scales with energy, as you well know (for by-standers here, John and I have teamed together in the Higgs Sensitivity Working Group four years ago: and I have to say he made me really blush once, when he spent words of praise on one bit of result I had gotten within that group - it was indeed about increasing the jet energy resolution!). Anyway. The fact that the H->bb at 160 would be almost twice as fat as the one at 90, means that a tenth of the rate of Z->bb decays in my plot, spread in a bump twice as wide, would be 20 times less tall. And the Z signal in my plot is "400 events" tall. So you get that you need to look for a 20-25ish event tall gaussian excess, spread over the region 130 to 190 GeV. Now, can we rule that out in my plot ? No. Because there are several points above the fit in the 160 GeV region. More importantly, the data-fit distribution shown in the inset of the plot shown in the post does not account for background uncertainties... All in all, John, I think you are being too nice by saying the MSSM H search should be done in our sample! But we will give it a look! Cheers, T. Hi John,

it’s nice to meet virtually here to discuss your signal and my non-signal :)
You did a clear back-of-the-envelope calculation, and I have little to object to it. Of course, one could try to make it a bit more precise (say, the efficiency at 160 GeV is larger than at 90, blah). The bottomline, though, I think is the one you already drew.

Indeed, one should see a signal a tenth of the Z->bb or so in our plot. The signal would have a width of 20 GeV or so, though, that is almost twice as large as the Z peak, because our resolution scales with energy, as you well know (for by-standers here, John and I have teamed together in the Higgs Sensitivity Working Group four years ago: and I have to say he made me really blush once, when he spent words of praise on one bit of result I had gotten within that group - it was indeed about increasing the jet energy resolution!).
Anyway. The fact that the H->bb at 160 would be almost twice as fat as the one at 90, means that a tenth of the rate of Z->bb decays in my plot, spread in a bump twice as wide, would be 20 times less tall.
And the Z signal in my plot is “400 events” tall.
So you get that you need to look for a 20-25ish event tall gaussian excess, spread over the region 130 to 190 GeV.

Now, can we rule that out in my plot ? No. Because there are several points above the fit in the 160 GeV region.

More importantly, the data-fit distribution shown in the inset of the plot shown in the post does not account for background uncertainties… All in all, John, I think you are being too nice by saying the MSSM H search should be done in our sample! But we will give it a look!

Cheers,
T.

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