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Author (down) Huang, J.W.; Madden, A.; Racco, D.; Reig, M.
Title Maximal axion misalignment from a minimal model Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 143 - 39pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract The QCD axion is one of the best motivated dark matter candidates. The misalignment mechanism is well known to produce an abundance of the QCD axion consistent with dark matter for an axion decay constant of order 10(12) GeV. For a smaller decay constant, the QCD axion, with Peccei-Quinn symmetry broken during inflation, makes up only a fraction of dark matter unless the axion field starts oscillating very close to the top of its potential, in a scenario called “large-misalignment”. In this scenario, QCD axion dark matter with a small axion decay constant is partially comprised of very dense structures. We present a simple dynamical model realising the large-misalignment mechanism. During inflation, the axion classically rolls down its potential approaching its minimum. After inflation, the Universe reheats to a high temperature and a modulus (real scalar field) changes the sign of its minimum dynamically, which changes the sign of the mass of a vector-like fermion charged under QCD. As a result, the minimum of the axion potential during inflation becomes the maximum of the potential after the Universe has cooled through the QCD phase transition and the axion starts oscillating. In this model, we can produce QCD axion dark matter with a decay constant as low as 6 x 10(9) GeV and an axion mass up to 1 meV. We also summarise the phenomenological implications of this mechanism for dark matter experiments and colliders.
Address [Huang, Junwu; Madden, Amalia; Racco, Davide] Perimeter Inst Theoret Phys, 31 Caroline St N, Waterloo, ON N2L 2Y5, Canada, Email: jhuang@perimeterinstitute.ca;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000586368800006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4592
Permanent link to this record
 
 
Author (down) Hooper, D.; Leane, R.K.; Tsai, Y.D.; Wegsman, S.; Witte, S.J.
Title A systematic study of hidden sector dark matter: application to the gamma-ray and antiproton excesses Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 163 - 38pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract In hidden sector models, dark matter does not directly couple to the particle content of the Standard Model, strongly suppressing rates at direct detection experiments, while still allowing for large signals from annihilation. In this paper, we conduct an extensive study of hidden sector dark matter, covering a wide range of dark matter spins, mediator spins, interaction diagrams, and annihilation final states, in each case determining whether the annihilations are s-wave (thus enabling efficient annihilation in the universe today). We then go on to consider a variety of portal interactions that allow the hidden sector annihilation products to decay into the Standard Model. We broadly classify constraints from relic density requirements and dwarf spheroidal galaxy observations. In the scenario that the hidden sector was in equilibrium with the Standard Model in the early universe, we place a lower bound on the portal coupling, as well as on the dark matter's elastic scattering cross section with nuclei. We apply our hidden sector results to the observed Galactic Center gamma-ray excess and the cosmic-ray antiproton excess. We find that both of these excesses can be simultaneously explained by a variety of hidden sector models, without any tension with constraints from observations of dwarf spheroidal galaxies.
Address [Hooper, Dan; Tsai, Yu-Dai] Fermilab Natl Accelerator Lab, Fermilab, Batavia, IL 60510 USA, Email: dhooper@fnal.gov;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000555828300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4491
Permanent link to this record
 
 
Author (down) Hoang, A.H.; Ruiz-Femenia, P.; Stahlhofen, M.
Title Renormalization group improved bottom mass from (gamma) sum rules at NNLL order Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 188 - 30pp
Keywords Heavy Quark Physics; Sum Rules; QCD
Abstract We determine the bottom quark mass from non-relativistic large-n gamma sum rules with renormalization group improvement at next-to-next-to-leading logarithmic order. We compute the theoretical moments within the vNRQCD formalism and account for the summation of powers of the Coulomb singularities as well as of logarithmic terms proportional to powers of alpha(s) ln(n). The renormalization group improvement leads to a substantial stabilization of the theoretical moments compared to previous fixed-order analyses, which did not account for the systematic treatment of the logarithmic alpha(s) ln(n) terms, and allows for reliable single moment fits. For the current world average of the strong coupling (alpha(s) (M-Z) = 0.1183 +/- 0.0010) we obtain M-b(1S) = 4.755 +/- 0.057(pert) +/- 0.009 alpha(s) +/- 0.003(exp) GeV for the bottom 1S mass and (m) over bar (b) ((m) over bar (b)) = 4.235 +/- 0.055(pert) +/- 0.003(exp) GeV for the bottom (MS) over bar mass, where we have quoted the perturbative error and the uncertainties from the strong coupling and the experimental data.
Address [Hoang, Andre H.; Ruiz-Femenia, Pedro; Stahlhofen, Maximilian] Univ Vienna, Fac Phys, A-1090 Vienna, Austria, Email: Andre.Hoang@univie.ac.at;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000310851300011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1231
Permanent link to this record
 
 
Author (down) Hirsch, M.; Reichert, L.; Porod, W.
Title Supersymmetric mass spectra and the seesaw scale Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 086 - 32pp
Keywords Supersymmetry Phenomenology
Abstract Supersymmetric mass spectra within two variants of the seesaw mechanism, commonly known as type-II and type-III seesaw, are calculated using full 2-loop RGEs and minimal Supergravity boundary conditions. The type-II seesaw is realized using one pair of 15 and (15) over bar superfields, while the type-III is realized using three copies of 24(M) superfields. Using published, estimated errors on SUSY mass observables attainable at the LHC and in a combined LHC+ILC analysis, we calculate expected errors for the parameters of the models, most notably the seesaw scale. If SUSY particles are within the reach of the ILC, pure mSugra can be distinguished from mSugra plus type-II or type-III seesaw for nearly all relevant values of the seesaw scale. Even in the case when only the much less accurate LHC measurements are used, we find that indications for the seesaw can be found in favourable parts of the parameter space. Since our conclusions crucially depend on the reliability of the theoretically forecasted error bars, we discuss in some detail the accuracies which need to be achieved for the most important LHC and ILC observables before an analysis, such as the one presented here, can find any hints for type-II or type-III seesaw in SUSY spectra.
Address [Hirsch, M; Reichert, L] Univ Valencia, CSIC, AHEP Grp, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000291364500018 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 685
Permanent link to this record
 
 
Author (down) Hirsch, M.; Malinsky, M.; Porod, W.; Reichert, L.; Staub, F.
Title Hefty MSSM-like light Higgs in extended gauge models Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 084
Keywords
Abstract It is well known that in the MSSM the lightest neutral Higgs h(0) must be, at the tree level, lighter than the Z boson and that the loop corrections shift this stringent upper bound up to about 130GeV. Extending the MSSM gauge group in a suitable way, the new Higgs sector dynamics can push the tree-level mass of h(0) well above the tree-level MSSM limit if it couples to the new gauge sector. This effect is further pronounced at the loop level and h(0) masses in the 140GeV ballpark can be reached easily. We exemplify this for a sample setting with a low-scale U(1)(R) x U(1)(B-L) gauge symmetry in which neutrino masses can be implemented via the inverse seesaw mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000301453400004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1027
Permanent link to this record
 
 
Author (down) Hirsch, M.; Lineros, R.A.; Morisi, S.; Palacio, J.; Rojas, N.; Valle, J.W.F.
Title WIMP dark matter as radiative neutrino mass messenger Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 149 - 18pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM; Neutrino Physics
Abstract The minimal seesaw extension of the Standard SU(3)(c)circle times SU(2)(L)circle times U(1)(Y) Model requires two electroweak singlet fermions in order to accommodate the neutrino oscillation parameters at tree level. Here we consider a next to minimal extension where light neutrino masses are generated radiatively by two electroweak fermions: one singlet and one triplet under SU(2)(L). These should be odd under a parity symmetry and their mixing gives rise to a stable weakly interactive massive particle (WIMP) dark matter candidate. For mass in the GeV-TeV range, it reproduces the correct relic density, and provides an observable signal in nuclear recoil direct detection experiments. The fermion triplet component of the dark matter has gauge interactions, making it also detectable at present and near future collider experiments.
Address [Hirsch, M.; Lineros, R. A.; Palacio, J.; Valle, J. W. F.] Univ Valencia, Edificio Inst Paterna, CSIC, Inst Fis Corpuscular,AHEP Grp, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000326047200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1623
Permanent link to this record
 
 
Author (down) Hirsch, M.; Krauss, M.E.; Opferkuch, T.; Porod, W.; Staub, F.
Title A constrained supersymmetric left-right model Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 009 - 22pp
Keywords Supersymmetry Phenomenology
Abstract We present a supersymmetric left-right model which predicts gauge coupling unification close to the string scale and extra vector bosons at the TeV scale. The subtleties in constructing a model which is in agreement with the measured quark masses and mixing for such a low left-right breaking scale are discussed. It is shown that in the constrained version of this model radiative breaking of the gauge symmetries is possible and a SM-like Higgs is obtained. Additional CP-even scalars of a similar mass or even much lighter are possible. The expected mass hierarchies for the supersymmetric states differ clearly from those of the constrained MSSM. In particular, the lightest down-type squark, which is a mixture of the sbottom and extra vector-like states, is always lighter than the stop. We also comment on the model's capability to explain current anomalies observed at the LHC.
Address [Hirsch, Martin] Univ Valencia, Inst Fis Corpuscular CSIC, AHEP Grp, Edificio Inst Paterna,Apartado 22085, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000371428600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2564
Permanent link to this record
 
 
Author (down) Hirsch, M.; Kernreiter, T.; Romao, J.C.; del Moral, A.V.
Title Minimal supersymmetric inverse seesaw: neutrino masses, lepton flavour violation and LHC phenomenology Type Journal Article
Year 2010 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 103 - 21pp
Keywords Rare Decays; Beyond Standard Model; Neutrino Physics; Supersymmetric Standard Model
Abstract We study neutrino masses in the framework of the supersymmetric inverse seesaw model. Different from the non-supersymmetric version a minimal realization with just one pair of singlets is sufficient to explain all neutrino data. We compute the neutrino mass matrix up to 1-loop order and show how neutrino data can be described in terms of the model parameters. We then calculate rates for lepton flavour violating (LFV) processes, such as μ-> e gamma and chargino decays to singlet scalar neutrinos. The latter decays are potentially observable at the LHC and show a characteristic decay pattern dictated by the same parameters which generate the observed large neutrino angles.
Address [Hirsch, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes ISI:000273959700030 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 509
Permanent link to this record
 
 
Author (down) Hirsch, M.; Joaquim, F.R.; Vicente, A.
Title Constrained SUSY seesaws with a 125 GeV Higgs Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 105 - 33pp
Keywords Higgs Physics; Rare Decays; Neutrino Physics; Supersymmetric Standard Model
Abstract Motivated by the ATLAS and CMS discovery of a Higgs-like boson with a mass around 125 GeV, and by the need of explaining neutrino masses, we analyse the three canonical SUSY versions of the seesaw mechanism (type I, II and III) with CMSSM boundary conditions. In type II and III cases, SUSY particles are lighter than in the CMSSM (or the constrained type I seesaw), for the same set of input parameters at the universality scale. Thus, to explain m(h0) similar or equal to 125 GeV at low energies, one is forced into regions of parameter space with very large values of m(0), M-1/2 or A(0). We compare the squark and gluino masses allowed by the ATLAS and CMS ranges for m(h0) (extracted from the 2011-2012 data), and discuss the possibility of distinguishing seesaw models in view of future results on SUSY searches. In particular, we briefly comment on the discovery potential of LHC upgrades, for squark/gluino mass ranges required by present Higgs mass constraints. A discrimination between different seesaw models cannot rely on the Higgs mass data alone, therefore we also take into account the MEG upper limit on BR(mu -> e gamma) and show that, in some cases, this may help to restrict the SUSY parameter space, as well as to set complementary limits on the seesaw scale.
Address [Hirsch, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000312198500040 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1301
Permanent link to this record
 
 
Author (down) Herrero-Garcia, J.; Rius, N.; Santamaria, A.
Title Higgs lepton flavour violation: UV completions and connection to neutrino masses Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 084 - 45pp
Keywords Beyond Standard Model; Higgs Physics; Neutrino Physics
Abstract We study lepton violating Higgs (HLFV) decays, first from the effective field theory (EFT) point of view, and then analysing the different high-energy realizations of the operators of the EFT, highlighting the most promising models. We argue why two Higgs doublet models can have a BR(h -> tau mu) similar to 0:01, and why this rate is suppressed in all other realizations including vector-like leptons. We further discuss HLFV in the context of neutrino mass models: in most cases it is generated at one loop giving always BR (h -> tau mu) < 10(-4) and typically much less, which is beyond experimental reach. However, both the Zee model and extended left-right symmetric models contain extra SU(2) doublets coupled to leptons and could in principle account for the observed excess, with interesting connections between HLFV and neutrino parameters.
Address [Herrero-Garcia, Juan] KTH Royal Inst Technol, AlbaNova Univ Ctr, Sch Engn Sci, Dept Theoret Phys, S-10691 Stockholm, Sweden, Email: juhg@kth.se;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000387843300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2862
Permanent link to this record