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Iniziativa Specifica Iniziativa specifica AAE (AstroAlteEnergie) - 2018 (sezioni di Pisa + Trieste + GranSasso) Linee di ricerca: • BSM physics: model building and phenomenology • Collider Physics • Dark Matter / Astro-particles • Cosmology / Inflation • Neutrino physics Responsabile Nazionale: Roberto Contino [sezione di Pisa (a partire dal 1 Ottobre 2016) ] e-mail: [email protected] Responsabili Locali: Stefano Bertolini [sezione di Trieste] e-mail: [email protected] Zurab Berezhiani [sezione LNGS/L’Aquila ] e-mail: [email protected] Componenti di Pisa per il 2018 (tutti al 100%)!! ! ! !!! Membri Permanenti 1. Roberto Contino Associato SNS 2. Alessandro Strumia Associato Dipartimento di Fisica 3. Enrico Trincherini Ricercatore SNS 4. Riccardo Barbieri ! Ordinario Emerito SNS (associato senior)!! ! Postdoc 5. Rashmish Mishra Postdoc INFN 6. Leonardo Trombetta Postdoc SNS ! Studenti Ph.D. 7. Kevin Max! Dottorando SNS 8. Andrea Mitridate Dottorando SNS 9. Alessandro Podo!! Dottorando SNS Borse Postdoc INFN assegnate ad AAE ! Nel 2017: alla sezione di Pisa Selezione svolta a fine Novembre 2016 Vincitore: Rashmish Mishra (attualmente postdoc a Maryland College Park, presa di servizio prevista per il 1/9/2017) ! Nel 2018: alla sezione di LNGS Selezione da svolgersi in autunno 2017 Richiesta finanziaria per il 2018 (missioni nazionali e internazionali): 13 k" Risultati dell’attività di Ricerca (Luglio 2016 - Giugno 2017) ! BSM: model building and phenomenology 1) Costruzione di modelli non-supersimmetrici che tentano di risolvere il problema della gerarchia (Higgs composto e modelli di Twin Higgs) Riccardo Barbieri, Lawrence J. Hall, Keisuke Harigaya. Effective Theory of Flavor for Minimal Mirror Twin Higgs arXiv:1706.05548 [hep-ph]. Roberto Contino, Davide Greco, Rakhi Mahbubani, Riccardo Rattazzi, Riccardo Torre. Precision Tests and Fine Tuning in Twin Higgs Models arXiv:1702.00797 [hep-ph]. Riccardo Barbieri, Lawrence J. Hall, Keisuke Harigaya. Minimal Mirror Twin Higgs JHEP 1611 (2016) 172. Francesco Sannino, Alessandro Strumia, Andrea Tesi, Elena Vigiani. Fundamental partial compositeness JHEP 1611 (2016) 029. Da: Contino, Greco, Mahbubani, Rattazzi, Torre arXiv:1702.00797 Nei modelli di Twin Higgs composto la massa dell’Higgs è quasi interamente t t˜ t˜ riprodotta dal contributo (calcolabile) infrarosso dei loop di top e twin top #%" ξ !=0!"#.1 #$" " LO Ex: per m =5TeV e ξ =0.1 #'" ∗ !"# [GeV] ! #&" NNLO IR = 74% ( 47% SM + 27% twin tops) "# IR ! ) ! 2 h ! m #"" NLO δ ( %" Curva NNLO presa da: $" Greco and Mimouni JHEP 1611 (2016) 108 !"" #""" !""" #"! m!! [GeV]! ()* " ∗ 2) Approcci alternativi al problema della gerarchia Giulio Maria Pelaggi, Francesco Sannino, Alessandro Strumia, Elena Vigiani. Naturalness of asymptotically safe Higgs arXiv:1701.01453 [hep-ph]. Alberto Salvio, Alessandro Strumia. Agravity up to infinite energy arXiv:1705.03896 [hep-th]. ! Fenomenologia BSM e collider physics 1) Studio di validità dell’approccio di teoria effettiva per fisica di precisione ai collider adronici Aleksandr Azatov, Roberto Contino, Camila S. Machado, Francesco Riva. Helicity selection rules and noninterference for BSM amplitudes Phys.Rev. D95 (2017) no.6, 065014. 2) Analisi del processo di Higgs pair production via Vector Boson Fusion a collider adronici (LHC e FCC-hh) Fady Bishara, Roberto Contino, Juan Rojo. Higgs pair production in vector-boson fusion at the LHC and beyond arXiv:1611.03860 [hep-ph]. Da: Bishara, Contino, Rojo arXiv:1611.03860 16 q q q Higgs pair production via VBF è un h h V h processo molto sensibile al coupling V V V V h V h hhVV e un buon test di nuova fisica h q q q 100 LHC s !14 TeV g ghhh 50 hhV V SM δc 1 δc3 1 % 2V SM SM ≡ ghhV V − ≡ ghhh − hh $ δc2V 1 1 Fig. 12 Posterior probability densities for δc2V at the LHC for L = 300 fb− (LHC14) and L = 3 ab− (HL-LHC) and for the FCC with pp 1 # 10 L = 10 ab− . Note the different scales of the axes in the two panels. " %& 5 hh 68% probability interval on δc2V $ 1 σbkg 3 σbkg pp × × # 1 δc3 " LHC [ 0.37, 0.45] [ 0.43, 0.48] 14 − − 0.5 HL-LHC [ 0.15, 0.19] [ 0.18, 0.20] − − "1.0 "0.5 0.0 0.5 1.0 FCC100 [0, 0.01] [ 0.01, 0.01] ! − Table 5 Expected precision (at 68% probability level) for the measurement of δc2V at the LHC and the FCC, assuming SM values of the Higgs couplings. We show results both for the nominal background cross section σbkg, and for the case in which this value is rescaled by a factor 3. value of the coefficients in bin i are given in Appendix D. We denote by π(c2V ) the prior probability distribution of the c2V coupling. As justified above, in the evaluation of Eq. (18) we set δB(S) = 0.15 (0.1) and assume that the two nuisance parameters are normally distributed. We have verified that assuming instead a log normal distribution leads to i i similar results. In addition, we take a Poissonian likelihood L(N Nobs) in each bin and assume the prior probability | 1 π(c2V ) to be uniform. The resulting posterior probabilities are shown in Fig. 12 for the LHC with L = 300 fb− 1 1 (LHC14) and L = 3 ab− (HL-LHC), and for the FCC with L = 10 ab− . To produce this figure, as well as to determine the values reported in Tabs. 5 and 6, we included all bins with at least one event. From Fig. 12, we can determine the expected precision for a measurement of δc2V at the LHC and the FCC in the case of SM values of the Higgs couplings. The 68% probability intervals for the determination of c2V at the LHC and the FCC are listed in Table 5. This is the central result of this work. To assess its robustness with respect to our estimate of the background cross sections, we also provide the same intervals in the case of an overall rescaling of the total background by a factor 3. Furthermore, we can also assess the effect of varying cV on the bound on δc2V by treating cV as a nuisance parameter and marginalizing over it. The leading effect of varying cV comes from the 2 (c2V cV ) term at the amplitude level – see Eq. 4 – and can be included using the parametrization of Eq. 8. The − 2 neglected dependence is sub-leading and arises from the interference of diagrams proportional to cV and cV c3.We take cV to be Gaussian distributed with a mean equal to 1 (i.e., its SM value) and a width equal to the 4.3%, 3.3%, and 2% at the LHC Run II, HL-LHC, and FCC respectively. In case of the LHC (both Run II and HL), the width of the Gaussian corresponds to the projected sensitivity from the two parameter fit by ATLAS [111]. The effect of marginalizing over cV is sub-leading in both LHC scenarios and weakens the bound on δc2V with respect to the bounds quoted in Table 5. We find that the results of Table 5 change by 2% for LHC14 and 7% for HL-LHC. The effect at the FCC is much larger causing the bound on δc2V to be O(0.04) rather than 0.01. This is not surprising and indicates that a joint likelihood would be required at the FCC. From Table 5, we find that the c2V coupling, for which there are currently no direct experimental constraints, 1 +45% can already be measured at the LHC with 300fb− with a reasonably good accuracy: 37% with 68% probability. This accuracy is only marginally degraded if the background is increased by a factor 3.− A better precision, of the +19% 1 order of 15%, is expected at the HL-LHC with 3ab− . Also, this estimate is robust against an overall rescaling of − 1 the background cross section. Finally, we find a very significant improvement at the FCC with 10ab− , where a measurement at the 1% level could be achieved providing an unprecedented test for our understanding of the Higgs sector. It is interesting to compare these results with the experimental precision expected on the fiducial VBF di-Higgs production cross section after all analysis cuts, expressed in terms of the signal strength parameter normalized to the SM result, µ = σ/σSM. Table 6 shows the 95% upper limits on µ for the nominal background cross section 3) Analisi ed interpretazione delle anomalie nella fisica del B Riccardo Barbieri, Christopher W. Murphy, Fabrizio Senia. B-decay Anomalies in a Composite Leptoquark Model Eur.Phys.J. C77 (2017) no.1, 8. Guido D'Amico, Marco Nardecchia, Paolo Panci, Francesco Sannino, Alessandro Strumia, Riccardo Torre, Alfredo Urbano. Flavour anomalies after the $R_{K^*}$ measurement arXiv:1704.05438 [hep-ph]. ! Dark Matter / Astro-particles 1) Analisi della formazione di bound state nel processo di annichilazione di Materia Oscura in particelle dello SM Andrea Mitridate, Michele Redi, Juri Smirnov, Alessandro Strumia. Cosmological Implications of Dark Matter Bound States JCAP 1705 (2017) no.05, 006. ! Cosmology / Inflation 1) Costruzione di modelli di evoluzione cosmologica privi di singolarità Paolo Creminelli, David Pirtskhalava, Luca Santoni, Enrico Trincherini. Stability of Geodesically Complete Cosmologies JCAP 1611 (2016) no.11, 047. 2) Scenario che propone una soluzione del problema della costante cosmologica attraverso un meccanismo di rilassamento cosmologico Lasma Alberte, Paolo Creminelli, Andrei Khmelnitsky, David Pirtskhalava, Enrico Trincherini. Relaxing the Cosmological Constant: a Proof of Concept JHEP 1612 (2016) 022. 3) Analisi aggiornata delle correzioni gravitazionali al decadimento del vuoto nella fase metastabile dello SM Aris Joti, Aris Katsis, Dimitris Loupas, Alberto Salvio, Alessandro Strumia, Nikolaos Tetradis, Alfredo Urbano. (Higgs) vacuum decay during inflation arXiv:1706.00792 [hep-ph]. Alberto Salvio, Alessandro Strumia, Nikolaos Tetradis, Alfredo Urbano. On gravitational and thermal corrections to vacuum decay JHEP 1609 (2016) 054.
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