Abstract
As we saw in the previous chapters, simplified models are a useful tool to interpret LHC and other experiments’ data in terms of a minimal theory of Dark Matter, which contains only the relevant degrees of freedom that can be probed in our searches.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
The initial configuration \(\chi \chi \) is a CP eigenstate with eigenvalue \(-1\):the DM particles are identical fermions and their wavefunction must be antisymmetric. In the limit of zero velocity \(L=0\) requires an antisymmetric opposite spin configuration corresponding to \(S=0\). Thus the CP eigenvalue of the \(\chi \chi \) is \((-1)^{2L+S+1}=-1\). In the final state \(f\overline{f}\) f and \(\overline{f}\) have opposite chiralities, implying opposite helicities if we neglect the fermion mass \(m_f\), and the total spin along that axis is \(+\)1. Thus the CP eigenvalue for the final state is \((-1)^{2L+S+1}=+1\). CP conservation thus forbids the annihilation of two DM particles into two massless fermions in the limit of zero velocity, if the fermion current preserves chirality (see also [6]).
- 2.
- 3.
- 4.
The simplest model that could provide a massive Majorana particle interacting with the \(Z'\) could be the following. We use the 2-component notation. We introduce a Majorana fermion \(\psi _0\) and two Weyl fermions \(\psi _1\), \(\psi _2\). \(\psi _1\) and \(\psi _2\) interact with the \(Z'\) with opposite charges, and we write a mass term (\(\psi _{2\,\alpha }\psi _1^\alpha +\) h.c.) that is both gauge invariant and Lorentz invariant. With just one Weyl spinor we would not manage to write a gauge invariant term. (A term like \(\psi _1^\dagger \psi _1\) would violate Lorentz symmetry.) The Lagrangian for these fields would be
where \(\Phi \) is the scalar field responsible of the BEH mechanism in the \(U(1)'\) sector. Notice that the third line, independently from the value of \(y_1\), \(y_2\), prevents us from writing (9.6) in terms of a Majorana spinor \(\left( {\begin{array}{c}\psi _1\\ \psi _2\end{array}}\right) \). Once \(\Phi \) assumes a vev v, the mass matrix for the triplet \((\psi _1,\psi _2, \psi _0)\) is
where M is a mass term for \(\psi _0\) that can possibly appear in (9.6). The diagonalisation of the mass matrix brings to a Majorana massive particle interacting with \(Z'\), which can be close to \(\psi _0\) if \(M, y_i v\ll m\). Notice that the terms proportional to v in (9.7) introduce a splitting in the mass matrix between what could be the L- and R-handed components of a Dirac spinor. Some theories of inelastic dark matter elaborate on the possibility that this mass splitting is small, and the lightest eigenstate could convert into the heavier one via inelastic scattering.
We conclude by stressing that the vector-like coupling of \(Z'\) to \(\psi _1\) and \(\psi _2\) ensures the cancellation of the gauge anomaly in the diagrams involving these fermions.
- 5.
We remark the following. If the \(Z'\) mass \(m_{Z'}\) is larger than a few TeV, the bounds shown in Fig. 9.3 and the following fall in a region in which the product \(g_{Z'}g_\chi ^{1/2}\) is necessarily \(\gtrsim 1\). This is in contrast with the fact that our \(Z'\) model has a rather large mediator width, and it must be \(g_{Z'}g_\chi ^{1/2} \lesssim 1\) in order to have \(\Gamma _{Z'}\lesssim m_{Z'}\). For this reason, with the present experimental sensitivity the lines of Fig. 9.8 correspond to a realistic physical situation only for \(m_{Z'}\sim \,\mathrm{few\ TeV}\).
- 6.
For instance, Ref. [58] practically exclude an area of \(10^\circ \) from consideration. Similarly, theoretical studies (see e.g. [59]) mask out \(1^\circ \) to \(2^\circ \) around the Galactic Centre. We do not show the Fermi-LAT Galactic Centre bounds on our plots because they are inferior to the Fermi-LAT dSph bounds. It is also worth mentioning that measurements of the dSphs are essentially foregrounds-free, which renders them extremely robust.
References
T. Jacques, A. Katz, E. Morgante, D. Racco, M. Rameez, A. Riotto, Complementarity of DM Searches in a Consistent Simplified Model: the Case of Z’, JHEP 071, 1610 (2016), arXiv:1605.06513
A. Manalaysay, L.U.X. The, dark matter search, Talk at IDM2016 (Sheffield, UK, 2016)
PICO Collaboration, C. Amole et al., Dark Matter Search Results from the PICO-60 CF \(_3\) I Bubble Chamber, Submitted to: Phys. Rev. D (2015), arXiv:1510.07754
IceCube Collaboration, M.G. Aartsen et al., Search for dark matter annihilations in the Sun with the 79-string IceCube detector, Phys. Rev. Lett. 110, no. 13 131302 (2013), arXiv:1212.4097
IceCube Collaboration, M.G. Aartsen et al., Improved limits on dark matter annihilation in the Sun with the 79-string IceCube detector and implications for supersymmetry, JCAP 022(04), 1604 (2016), arXiv:1601.00653
M. Drees, M.M. Nojiri, The Neutralino relic density in minimal N=1 supergravity, Phys. Rev. D47, 376–408 (1993), arXiv:hep-ph/9207234
M. Cirelli, N. Fornengo, A. Strumia, Minimal dark matter, Nucl. Phys. B753, 178–194 (2006), arXiv:hep-ph/0512090
M. Cirelli, A. Strumia, Minimal Dark Matter: Model and results, New J. Phys. 11, 105005 (2009), arXiv:0903.3381
N. Arkani-Hamed, S. Dimopoulos, Supersymmetric unification without low energy supersymmetry and signatures for fine-tuning at the LHC, JHEP 06, 073 (2005), arXiv:hep-th/0405159
G.F. Giudice, A. Romanino, Split supersymmetry, Nucl. Phys. B699, 65–89 (2004), arXiv:hep-ph/0406088. [Erratum: Nucl. Phys. B 706, 487 (2005)]
A. Arvanitaki, N. Craig, S. Dimopoulos, G. Villadoro, Mini-Split, JHEP 02 (2013), p. 126, arXiv:1210.0555
N. Arkani-Hamed, A. Gupta, D.E. Kaplan, N. Weiner, T. Zorawski, Simply Unnatural Supersymmetry, arXiv:1212.6971
Z. Bern, P. Gondolo, M. Perelstein, Neutralino annihilation into two photons, Phys. Lett. B411, 86–96 (1997), arXiv:hep-ph/9706538
L. Bergstrom, P. Ullio, Full one loop calculation of neutralino annihilation into two photons, Nucl. Phys. B504, 27–44 (1997), arXiv:hep-ph/9706232
O. Lebedev, Y. Mambrini, Axial dark matter: The case for an invisible Z’, Phys. Lett. B734, 350–353 (2014), arXiv:1403.4837
F. Kahlhoefer, K. Schmidt-Hoberg, T. Schwetz, S. Vogl, Implications of unitarity and gauge invariance for simplified dark matter models, JHEP 02, 016 (2016), arXiv:1510.02110. [JHEP02,016(2016)]
N.F. Bell, Y.Cai, R.K. Leane, Mono-W Dark Matter Signals at the LHC: Simplified Model Analysis, JCAP 1601, no. 01 051 (2016), arXiv:1512.00476
O. Buchmueller, M.J. Dolan, S.A. Malik, C. McCabe, Characterising dark matter searches at colliders and direct detection experiments: Vector mediators, JHEP 037, 1501 (2015), arXiv:1407.8257
M. Blennow, J. Herrero-Garcia, T. Schwetz, S. Vogl, Halo-independent tests of dark matter direct detection signals: local DM density, LHC, and thermal freeze-out, JCAP 1508, no. 08 039 (2015), arXiv:1505.05710
A. Alves, S. Profumo, F.S. Queiroz, The dark \(Z^{\prime }\) portal: direct, indirect and collider searches, JHEP 1404, 063 (2014), arXiv:1312.5281
A. Alves, A. Berlin, S. Profumo, F.S. Queiroz, Dark Matter Complementarity and the \(Z^\prime \) Portal, Phys. Rev. D92, no.8 083004 (2015), arXiv:1501.03490
A. Alves, A. Berlin, S. Profumo, F.S. Queiroz, Dirac-fermionic dark matter in U \((1)_{X}\) models, JHEP 10, 076 (2015), arXiv:1506.06767
H. An, X. Ji, L.-T. Wang, Light Dark Matter and Z’ Dark Force at Colliders, JHEP 07, 182 (2012), arXiv:1202.2894
H. An, R. Huo, L.-T. Wang, Searching for Low Mass Dark Portal at the LHC, Phys. Dark Univ. 2, 50–57 (2013), arXiv:1212.2221
M.T. Frandsen, F.Kahlhoefer, A.Preston, S.Sarkar, K. Schmidt-Hoberg, LHC and Tevatron Bounds on the Dark Matter Direct Detection Cross-Section for Vector Mediators, JHEP 07, 123 (2012), arXiv:1204.3839
G. Arcadi, Y. Mambrini, M.H.G. Tytgat, B. Zaldivar, Invisible \(Z^\prime \) and dark matter: LHC vs LUX constraints, JHEP 03, 134 (2014), arXiv:1401.0221
I.M. Shoemaker, L. Vecchi, Unitarity and Monojet Bounds on Models for DAMA, CoGeNT, and CRESST-II, Phys.Rev. D86, 015023 (2012), arXiv:1112.5457
M.T. Frandsen, F.Kahlhoefer, S.Sarkar, K. Schmidt-Hoberg, Direct detection of dark matter in models with a light \(Z^\prime \), JHEP 09, 128 (2011), arXiv:1107.2118
P. Gondolo, P. Ko, Y. Omura, Light dark matter in leptophobic \(Z^\prime \) models, Phys. Rev. D85, 035022 (2012), arXiv:1106.0885
M. Fairbairn, J. Heal, Complementarity of dark matter searches at resonance, Phys. Rev. D90, no. 11 115019 (2014), arXiv:1406.3288
P. Harris, V.V. Khoze, M. Spannowsky, C. Williams, Constraining Dark Sectors at Colliders: Beyond the Effective Theory Approach, Phys. Rev. D 91, 055009 (2015), arXiv:1411.0535
M. Chala, F. Kahlhoefer, M. McCullough, G. Nardini, K. Schmidt-Hoberg, Constraining Dark Sectors with Monojets and Dijets, JHEP 07,089 (2015), arXiv:1503.05916
T. Jacques, K. Nordström, Mapping monojet constraints onto Simplified Dark Matter Models, JHEP 06, 142 (2015), arXiv:1502.05721
A.J. Brennan, M.F. McDonald, J. Gramling, T.D. Jacques, Collide and Conquer: Constraints on Simplified Dark Matter Models using Mono-X Collider Searches, JHEP 1605 (112), (2016), arXiv:1603.01366
H. Dreiner, D. Schmeier, J. Tattersall, Contact Interactions Probe Effective Dark Matter Models at the LHC, Europhys. Lett. 102, 51001 (2013), arXiv:1303.3348
K. Ghorbani, H. Ghorbani, Two-portal Dark Matter, Phys. Rev. D91, no. 12 123541 (2015), arXiv:1504.03610
S. Weinberg, The quantum theory of fields. Vol. 2: Modern applications (Cambridge University Press, 2013)
F. D’Eramo, B.J. Kavanagh, P. Panci, You can hide but you have to run: direct detection with vector mediators, JHEP 1608, 111 (2016), arXiv:1605.04917
P. Gondolo, G. Gelmini, Cosmic abundances of stable particles: Improved analysis. Nucl. Phys. B 360, 145–179 (1991)
K. Griest, D. Seckel, Three exceptions in the calculation of relic abundances. Phys. Rev. D 43, 3191–3203 (1991)
Planck Collaboration, P.A.R. Ade et al., Planck 2015 results. XIII. Cosmological parameters, Astron. Astrophys. A 13, 594 (2016), arXiv:1502.01589
A.L. Fitzpatrick, W. Haxton, E. Katz, N. Lubbers, Y. Xu, The Effective Field Theory of Dark Matter Direct Detection, JCAP 1302,004 (2013), arXiv:1203.3542
M. Cirelli, E. Del Nobile, P. Panci, Tools for model-independent bounds in direct dark matter searches, JCAP 1310,019 (2013), arXiv:1307.5955
U. Haisch, F. Kahlhoefer, On the importance of loop-induced spin-independent interactions for dark matter direct detection, JCAP 1304,050 (2013), arXiv:1302.4454
CMS Collaboration, V. Khachatryan et al., Search for physics beyond the standard model in dilepton mass spectra in proton-proton collisions at \( \sqrt{s}=8 \) TeV, JHEP 04, 025 (2015), arXiv:1412.6302
CMS Collaboration, S. Chatrchyan et al., Measurement of inclusive W and Z boson production cross sections in pp collisions at \(\sqrt{s}\) = 8 TeV, Phys. Rev. Lett. 112, 191802 (2014), arXiv:1402.0923
J. Alwall, R. Frederix, S. Frixione, V. Hirschi, F. Maltoni, O. Mattelaer, H.S. Shao, T. Stelzer, P. Torrielli, M. Zaro, The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations, JHEP 07, 079 (2014), arXiv:1405.0301
CMS Collaboration Collaboration, Search for a Narrow Resonance Produced in 13 TeV pp Collisions Decaying to Electron Pair or Muon Pair Final States, Technical Report CMS-PAS-EXO-15-005, CERN, Geneva, 2015
CMS Collaboration, V. Khachatryan et al., Search for dark matter, extra dimensions, and unparticles in monojet events in proton-proton collisions at \(\sqrt{s} = 8\) TeV, Eur. Phys. J. C75, no. 5 235 (2015), arXiv:1408.3583
G. Busoni, A. De Simone, E. Morgante, A. Riotto, On the Validity of the Effective Field Theory for Dark Matter Searches at the LHC, Phys.Lett. B728, 412–421 (2014), arXiv:1307.2253
G. Busoni, A. De Simone, J. Gramling, E. Morgante, A. Riotto, On the Validity of the Effective Field Theory for Dark Matter Searches at the LHC, Part II: Complete Analysis for the s-channel, JCAP 1406, 060 (2014), arXiv:1402.1275
D. Racco, A. Wulzer, F. Zwirner, Robust collider limits on heavy-mediator Dark Matter, JHEP 05, 009 (2015), arXiv:1502.04701
O. Buchmueller, M.J. Dolan, C. McCabe, Beyond effective field theory for dark matter searches at the LHC, JHEP 1401, 025 (2014), arXiv:1308.6799
DES, Fermi-LAT Collaboration, A. Drlica-Wagner et al., Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data, Astrophys. J. 809, no. 1 L4 (2015), arXiv:1503.02632
Fermi-LAT Collaboration, M. Ackermann et al., Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi Large Area Telescope Data, Phys. Rev. Lett. 115, no. 23 231301 (2015), arXiv:1503.02641
J.F. Navarro, C.S. Frenk, S.D.M. White, A Universal density profile from hierarchical clustering, Astrophys. J. 490, 493–508 (1997), arXiv:astro-ph/9611107
HESS Collaboration, H. Abdallah et al., Search for dark matter annihilations towards the inner Galactic halo from 10 years of observations with H.E.S.S, Phys. Rev. Lett. 117(11), 111301 (2016), arXiv:1607.08142
Fermi-LAT Collaboration, M. Ackermann et al., Constraints on the Galactic Halo Dark Matter from Fermi-LAT Diffuse Measurements, Astrophys. J. 761, 91 (2012), arXiv:1205.6474
T. Daylan, D.P. Finkbeiner, D. Hooper, T. Linden, S.K.N. Portillo, N.L. Rodd, T.R. Slatyer, The characterization of the gamma-ray signal from the central Milky Way: A case for annihilating dark matter, Phys. Dark Univ. 12, 1–23 (2016), arXiv:1402.6703
T. Cohen, M. Lisanti, A. Pierce, T.R. Slatyer, Wino Dark Matter Under Siege, JCAP 1310, 061 (2013), arXiv:1307.4082
J. Fan, M. Reece, In Wino Veritas? Indirect Searches Shed Light on Neutralino Dark Matter, JHEP 10, 124 (2013), arXiv:1307.4400
M. Cirelli, G. Corcella, A. Hektor, G. Hutsi, M. Kadastik, P. Panci, M. Raidal, F. Sala, A. Strumia, PPPC 4 DM ID: A Poor Particle Physicist Cookbook for Dark Matter Indirect Detection, JCAP 1130, 051 (2011), arXiv:1012.4515. [Erratum: JCAP1210, E01(2012)]
IceCube Collaboration, A. Achterberg et al., First Year Performance of The IceCube Neutrino Telescope, Astropart. Phys. 26, 155–173 (2006), arXiv:astro-ph/0604450
J. Braun, J. Dumm, F. De Palma, C. Finley, A. Karle, T. Montaruli, Methods for point source analysis in high energy neutrino telescopes, Astropart. Phys. 29, 299–305 (2008), arXiv:0801.1604
IceCube Collaboration, M. Rameez et al., Search for dark matter annihilations in the Sun using the completed IceCube neutrino telescope (2015), http://pos.sissa.it/archive/conferences/236/1209/ICRC2015_1209.pdf
G. Punzi, Comments on likelihood fits with variable resolution, eConf C030908, WELT002 235 (2004), arXiv:physics/0401045
K. Hagiwara, R.D. Peccei, D. Zeppenfeld, K. Hikasa, Probing the Weak Boson Sector in e+ e- –> W+ W-. Nucl. Phys. B 282, 253–307 (1987)
G.J. Gounaris, J. Layssac, F.M. Renard, New and standard physics contributions to anomalous Z and gamma selfcouplings, Phys. Rev. D62, 073013 (2000), arXiv:hep-ph/0003143
R. Catena, B. Schwabe, Form factors for dark matter capture by the Sun in effective theories, JCAP 1504, no. 04 042 (2015), arXiv:1501.03729
J. Blumenthal, P. Gretskov, M. Krämer, C. Wiebusch, Effective field theory interpretation of searches for dark matter annihilation in the Sun with the IceCube Neutrino Observatory, Phys. Rev. D91, no. 3 035002 (2015), arXiv:1411.5917
J. Heisig, M. Krämer, M. Pellen, C. Wiebusch, Constraints on Majorana Dark Matter from the LHC and IceCube, Phys. Rev. D93, no. 5 055029 (2016), arXiv:1509.07867
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2017 Springer International Publishing AG
About this chapter
Cite this chapter
Morgante, E. (2017). A U(1)’ Gauge Mediator. In: Aspects of WIMP Dark Matter Searches at Colliders and Other Probes. Springer Theses. Springer, Cham. https://doi.org/10.1007/978-3-319-67606-7_9
Download citation
DOI: https://doi.org/10.1007/978-3-319-67606-7_9
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-67605-0
Online ISBN: 978-3-319-67606-7
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)