Direct Detection of the Dark Mediated DM

Transcription

1 Direct Detection of the Dark Mediated DM Yuhsin Tsai In collaboration with David Curtin, Ze ev Surujon, and Yue Zhao and 1402.XXXX UC Davis Jan

2 Main questions χ χ How does the direct detection look like? φ N N

3 Main questions χ χ How does the direct detection look like? φ What kind of models can give this process? N N

4 Main questions φ φ How does the direct detection look like? What kind of models can give this process? q q What is the bound on this light scalar - quark coupling? dark mediator Dark Matter

5 !-Nucleon Cross Section [cm 2 ] Current DM experiments J. Billard and E. Figueroa-Feliciano (13) direct FERMI indirect LUX collider CMS Preliminary CMS, CMS, s = 7 TeV, 5.1 fb s = 8 TeV, 19.5 fb CoGeNT SIMPLE 2012 COUPP 2012 CDMS II (!# Spin Independent, Vector Operator 1 XENON0 2 M! µ!)(q# q) µ 2 " [GeV/c 2 ] 3

6 !-Nucleon Cross Section [cm 2 ] Current DM experiments J. Billard and E. Figueroa-Feliciano (13) direct FERMI indirect LUX collider CMS Preliminary -38 CMS, s = 7 TeV, 5.1 fb -1 irreducible neutrino-background sets a lower bound on the discovery CMS, s = 8 TeV, 19.5 fb CoGeNT SIMPLE 2012 (!# Spin Independent, Vector Operator COUPP 2012 CDMS II XENON0 M! µ!)(q# q) µ 2 " [GeV/c 2 ] 3

7 !-Nucleon Cross Section [cm 2 ] Current DM experiments J. Billard and E. Figueroa-Feliciano (13) direct FERMI indirect LUX collider CMS Preliminary -38 CMS, s = 7 TeV, 5.1 fb -1 irreducible neutrino-background sets a lower bound on the discovery assume 2 to 2 scatterings with a contact DM-quark coupling CMS, s = 8 TeV, 19.5 fb CoGeNT SIMPLE 2012 (!# Spin Independent, Vector Operator COUPP 2012 CDMS II XENON0 M! µ!)(q# q) µ 2 " [GeV/c 2 ] 3

8 Useful inconsistencies The inconsistencies between different experiments may reflect the detailed structure of the dark sector σ 2 2 n σ 2 2 n σ γ σ 2 2 n m 2 m DM m DM m 1 Existing ideas: exothermic DM, isospin violation, non-standard form factors, multi-component DM,... all assume 2to2 scattering so far It is important to explore a more complete set of DM models to explain the future data

9 Missing ingredient: different topology The exotic scattering process can provide new tools in understanding different experimental results χ χ σ 2 2 n for example φ N N m DM the recoil spectrum has a non-trivial m N dependence get different DM masses when assuming a WIMP-like process

10 A model building motivation It is natural to have a dark mediator in the dark sector φ φ q q dark mediator Dark Matter

11 A model building motivation It is natural to have a dark mediator in the dark sector χ χ φ φ q q dark mediator Dark Matter A natural way to have the 2 to 3 scattering

12 Other ways of getting 2to3? Not easy... χ χ χ χ χ χ loop q q q q q q strong bounds on light singlet scalars. hard to avoid the 2 to 2 scattering the loop suppression makes it hard to have a large cross section derivative couplings give velocity suppressions, assume DM doesn t carry SM charges Focus on the dmdm model in this talk

13 dmdm model with vectorized quarks φ 1 φ 2 φ 2 Qq Λ + y χ χχφ+ h.c. Λ = M 2 Q y Q y q y Qq v assume φ 1 = φ 2 = φ, y Q = y q = y Qq =1 in the mass basis for simplicity there is a 0.1% tuning on the light quark yukawa from the φ loop assume the effective scalar-quark coupling is flavor universal in the mass basis

14 Pseudo Light Dark Matter at direct detections

15 Direct detection in MadGraph Si-detector, easy to get, everyone can reproduce the result... To obtain the recoil spectrum generate the DM-quark scattering using MG5 multiply the cross section with the nuclear form factor convolute the result with velocity distribution and Helm Form Factor for 2 to 2 contact operator dr de r = N T ρ χ m χ dv vf(v) dσ N de r dr de r = 1 2 σn SI m vmax N µ 2 N T ρ χ A 2 F 2 (E r ) nχ m χ v min (E r ) dv 1 v f(v)

16 Recoil energy spectrum For a given DM energy standard 2 to 2 contact operator 2 to 3 contact operator d Σ d Er 42 cm kev d Σ d Er 24 cm kev m N 28, mχ, EΧ kev, 2to2 contact Er kev m N 28, mχ, EΧ kev, heavy mediator dσ de R = M 2 m2 N m2 χ Λ 4 for E max r M 2 32π m 2 χ m N v 2 χχ qq Λ 2 χγ µ χ qγ µ q Λ 2 = 2µ2 Nχ m N v 2 2 to 3 light mediator d Σ d Er 40 cm kev Er kev m N 28, mχ, EΧ kev, light mediator Er kev

17 Recoil energy spectrum For a given DM energy standard 2 to 2 contact operator 2 to 3 contact operator d Σ d Er 42 cm kev d Σ d Er 24 cm kev m N 28, mχ, EΧ kev, 2to2 contact Er kev m N 28, mχ, EΧ kev, heavy mediator dσ de R = M 2 m2 N m2 χ Λ 4 for E max r M 2 32π m 2 χ m N v 2 χχ qq Λ 2 χγ µ χ qγ µ q Λ 2 = 2µ2 Nχ m N v 2 2 to 3 light mediator d Σ d Er 40 cm kev Er kev m N 28, mχ, EΧ kev, light mediator 2to2 after f(v) and F m N =28GeV(Silicon) Er kev

18 2to3 scattering: contact vs. dmdm d Σ d Er 24 cm kev m N 28, mχ, EΧ kev, heavy mediator Er kev d Σ d Er 40 cm kev m N 28, mχ, EΧ kev, light mediator Er kev dσ 2 3 de R dσ 2 3 de R light heavy m 4 Φ (m N E R ) 2 m4 Φ p N 4 light contact Χ N Χ N Φ, N 28, mχ GeV, EΧ kev ratio 0.22 E r Er kev coming from the light mediator s propagator

19 Approximation of the spectrum d Σ d Er 24 cm kev m N 28, mχ, EΧ kev, heavy mediator m 2 N E R 1 2 E R /ER max Er kev d Σ d Er 40 cm kev m N 28, mχ, EΧ kev, light mediator E 1 R 1 2 E R /ER max Er kev with E max R = µ2 χn 2 m N v 2

20 A nice description of the Erecoil

21 A nice description of the Erecoil

22 A nice description of the Erecoil Three ingredients give the spectrum 1. phase space with φ carrying away some energy II. III. ER max E 2 R relates to the DM-nucleus mass from the propagator of light mediator

23 Mappings between 2to2 & 2to3 dσ der cm2 0.2 kev 36 before velocity distribution & form factor dmdm WIMP 50 5 Green: Blue: Red: CDMS-Si, after velocity distribution & form factor kev E r E r kev lack of events makes it hard to distinguish the shape difference in detail heavy dmdm looks like a light WIMP DM since the m χ of dmdm only shows up in µ χn of the spectrum, the spectrum is insensitive to the DM mass when the true m χ µ χn

24 Mappings between 2to2 & 2to3 dσ der cm2 0.2 kev 36 before velocity distribution & form factor dmdm WIMP 50 5 Green: Blue: Red: CDMS-Si, after velocity distribution & form factor kev E r E r kev lack of events makes it hard to distinguish the shape difference in detail heavy dmdm looks like a light WIMP DM since the m χ of dmdm only shows up in µ χn of the spectrum, the spectrum is insensitive to the DM mass when the true m χ µ χn

25 Pseudo-light Dark Matter 40 m 2 2 GeV XENON0 LUX CDMS Si CDMSlite m 2 3 GeV 0 GeV DM fakes a GeV WIMP different masses obtained by different experiments A single experiment cannot get the mass right. Multiple experiments are necessary for the mass measurement.

26 Interaction vs. mass σ y χ Λ 2 for DM as a thermal relic Λ > 20 TeV is given by the cooling constraints

27 Loop-induced 2 to 2 process The simplest model generates a 2 to 2 scattering 1 4 TeV TeV 2 CDMS Si Χ CDM & 20 TeV CDMSlite 1 6 TeV 2 XENON0 y Χ TeV TeV 2 LUX N 2 3 N 2 2 & 20 TeV 1 9 TeV 2 Irreducible neutrino BG m DM GeV Can be avoided in the heavylight model

28 Interaction vs. mass σ y χ Λ 2 for 2 to 3 > 2 to 2 Λ > 20 TeV is given by the cooling constraints

29 Interaction vs. mass σ y χ Λ 2 for 2 to 3 > 2 to 2 Λ > 20 TeV is given by the cooling constraints Simplest dmdm

30 Various Constraints on dmdm φ 1 φ 2

31 Various Constraints on dmdm DM self-interaction bounds DM relic abundance ΩX φ 1 φ 2

32 Various Constraints on dmdm DM self-interaction bounds DM relic abundance ΩX LHC bounds φ 1 φ 2

33 Various Constraints on dmdm DM self-interaction bounds DM relic abundance ΩX LHC bounds φ 1 φ 2 Ωϕ BBN: Neff Structure Formation

34 Various Constraints on dmdm DM self-interaction bounds DM relic abundance ΩX LHC bounds φ 1 φ 2 Solar Heat Transfer & Cooling Supernova Cooling White Dwarf Cooling Neutron Star Cooling Fixed Target Experiments & Beam Dumps Meson Decays Zϕϕ coupling Ωϕ BBN: Neff Structure Formation

35 Various Constraints on dmdm φ 2 Qq Λ y χ m φ We will only discuss the Λ bounds that are stronger than Λ > TeV in this talk

36 Various Constraints on dmdm DM self-interaction bounds DM relic abundance ΩX LHC bounds bullet cluster: thermal relic: y χφ < 1 y χ (m χ /GeV) 1/2 φ 1 φ 2 dijet: M Q > 1.5 TeV monojet: Λ > 6 TeV Solar Heat Transfer & Cooling Supernova Cooling White Dwarf Cooling Neutron Star Cooling Fixed Target Experiments & Beam Dumps Meson Decays Zϕϕ coupling Λ bounds are weaker than TeV Ωϕ BBN: Neff Structure Formation

37 Cosmological Constraints : Neff φ decoupled from thermal bath at If the decoupling happens just before the BBN, Neff has a from the current measurement T freeze φ 2/3 Λ > MeV TeV 2 σ deviation Plank+WMAP+HighL This can be relaxed when having symmetry φ φ, χ e iπ/2 χ φ as a real scalar charged under a Z4 so the deviation becomes small

38 Ω φ & the structure formation The φ density gives g φ =2, g S 12 This requires density if φ m φ < ev for having no significant contribution to the does not decay φ was a collisionless particle during the structure formation (~ ev). It only generates Landau damping to the primordial density fluctuations with a FS-length similar to neutrinos φ satisfies similar constraints as a light sterile neutrino Can also make φ φ F µν F µν /Λ decay by having

39 Cooling Constraints white dwarf supernovae the Sun neutron star

40 Stellar cooling: generalities If m φ T the scalar can be produced inside of stars. A production process X1 X2 ϕ +... yields rϕ = nx1 nx2 c σϕprod ϕs per unit volume per unit time. If we know the radial profiles of stellar density, temperature and composition we can find the total ϕ production rate for the star (assuming ϕ does not significantly alter stellar evolution). In the absence of significant ϕ-destroying processes, this is equal to the equillibrium total ϕ loss rate.

41 Stellar cooling: generalities If m φ T the scalar can be produced inside of stars. A production process X1 X2 ϕ +... yields rϕ = nx1 nx2 c σϕprod ϕs per unit volume per unit time. If we know the radial profiles of stellar density, temperature and composition we can find the total ϕ production rate for the star (assuming ϕ does not significantly alter stellar evolution). In the absence of significant ϕ-destroying processes, this is equal to the equillibrium total ϕ loss rate.

42 Stellar cooling: generalities If m φ T the scalar can be produced inside of stars. A production process X1 X2 ϕ +... yields rϕ = nx1 nx2 c σϕprod ϕs per unit volume per unit time. If we know the radial profiles of stellar density, temperature and composition we can find the total ϕ production rate for the star (assuming ϕ does not significantly alter stellar evolution). In the absence of significant ϕ-destroying processes, this is equal to the equillibrium total ϕ loss rate.

43 Stellar cooling: generalities If m φ T the scalar can be produced inside of stars. A production process X1 X2 ϕ +... yields rϕ = nx1 nx2 c σϕprod ϕs per unit volume per unit time. If we know the radial profiles of stellar density, temperature and composition we can find the total ϕ production rate for the star (assuming ϕ does not significantly alter stellar evolution). In the absence of significant ϕ-destroying processes, this is equal to the equillibrium total ϕ loss rate.

44 Stellar cooling: generalities If m φ T the scalar can be produced inside of stars. A production process X1 X2 ϕ +... yields rϕ = nx1 nx2 c σϕprod ϕs per unit volume per unit time. If we know the radial profiles of stellar last scattering density, temperature T and composition we can find the total ϕ production rate for the star (assuming ϕ does not significantly alter stellar evolution). In the absence of significant ϕ-destroying processes, this is equal to the equillibrium total ϕ loss rate. φ T ls φ(t ls ) stay thermalized until this radius This allows us to compute the energy lost due to ϕ emission.

45 Log Σ pb NΦ NΦ: Xe Fe Si C He p,n Λ = TeV NΝ NΝ: Xe Fe Si C He n p pp ppφφ Γp pφφ pγ pγ eγ eγ rough estimate of ΓΓ ΦΦ E Φ,Ν,Γ,p MeV Compute ϕ low-energy scattering and production cross sections analytically and in MadGraph. with qqφφ Λ B 2 =1 0

46 The Sun Core temperature is about T ~ 1 kev The most important ϕ production process is Ɣ N N ϕ ϕ For Λ = TeV, ϕ decouples at r ~ 0.7 x Rsun where T ~ 0.1 kev solar ϕ luminosity < 1% photon luminosity requires Λ > 1 TeV. Need the heat transfer of φ to be much smaller than the photon s 1 F φ n p c σ pγ pφφ t esc γ F γ 2 TeV Λ 2 No significant constraint

47 White Dwarfs Core temperature T ~ 1 - kev The White Dwarf Luminosity Function tells us how fast they cool. Ɣ cooling Observational data in good agreement with standard cooling theory! most WDs live here Need the scalar cooling to be much smaller than the photon cooling. Dreiner, Fortin, Isern, Ubaldi (13 )

48 Thank you!! Max Katz (graduate student of Michael SB) helped us by simulating the evolution of a sun-like star to a typical solar mass WD using the stellar evolution code (stellar astrophysics gold standard ). When our test dwarf has 0.1 x solar luminosity (very young and hot) ϕ power output is < % total WD luminosity if Ɣ cooling Λ > 20 TeV qqφφ Λ most WDs live here (ϕ emission even less important at lower core temperature)

49 Neutron Stars Lots of ϕ production in neutron star core via nn nnφφ The scattering only happens around the Fermi surface of neutrons f n (E) = exp( E µ T ) fn E Μ 60, T Energy

50 Neutron Stars Lots of ϕ production in neutron star core via nn nnφφ The scattering only happens around the Fermi surface of neutrons f n (E) = The neutrons scattering then is suppressed by a factor (T/µ) 2 6 which gives a small production rate exp( E µ T ) fn E Μ 60, T µ Energy T No significant constraint

51 Supernovae φ φ Qq Λ while σ N φ 1 Λ 2 σ N ν T 2 m 4 W The free streaming length L φ L ν φ then is trapped inside SN and gives no significant cooling comparing to neutrinos Λ 6 TeV Gives an upper bound Log Σ pb NΦ NΦ: Xe Fe Si C He p,n NΝ NΝ: Xe Fe Si C He n p pp ppφφ Γp pφφ pγ pγ eγ eγ rough estimate of ΓΓ ΦΦ E Φ,Ν,Γ,p MeV

52 Bound on the dmdm model Λ > 20 Tev and yx correct value for DM relic density 1 1 TeV TeV 2 CDMS Si CDMSlite y Χ TeV 2 XENON0 Χ CDM & 20 TeV Λ > 20 Tev and yx small enough to ensure subdominant TeV TeV TeV 2 N 2 3 N 2 2 & 20 TeV LUX Irreducible neutrino BG m DM GeV

53 Other possible uses For reconciling CDMS-Si and LUX σ 2 2 n χ χ CDMS φ O() cm m DM N N XENON if this is the case, having a larger detector will not help! Λ < GeV the φ F µν F µν /Λ coupling needs to be large, with unless the DM velocity is large (~ 0.01) so the Λ can be of TeV scale

54 Other possible uses For reconciling CDMS-Si and LUX σ 2 2 n χ χ accepted φ O() cm m DM N N vetoed if this is the case, having a larger detector will not help! Λ < GeV the φ F µν F µν /Λ coupling needs to be large, with unless the DM velocity is large (~ 0.01) so the Λ can be of TeV scale

55 Other possible uses For different masses from the direct/indirect detections σ γ χ γ χ χ σ 2 2 n m 1 m 2 m 2 >m 1 χ γ N N DM looks lighter in a direct detection when being fitted as 2to2 v-suppression from derivative couplings makes σ n too small

56 Conclusion dmdm is the first DM model featuring 2 3 direct detection, and hence adds new kinematics to model builder s tool box. Heavy DM candidates fake different light WIMPs at different detectors. New searching strategies will be necessary. Cosmo + Astro sets significant constraints, but large regions of detectable parameter space remain. The bound can be relaxed by the heavylight setup. Many possible applications of the dmdm model can be used for direct detections

57 Backup

58 A less constrained model So far we only consider the simplest case with a single scalar

59 A less constrained model So far we only consider the simplest case with a single scalar heavylight model with φ h φ l m φh 1 MeV, m φl < 1 kev y φ l q < 0.1 to avoid the sizable stellar production of φ y φ h q y φ l Q Moreover, if y χφl, y φ h Q < 3, the loop-induced 2 to 2 process will be < % of the 2 to 3 while keeping the large σ 2 3 φ h q φ h ψ q ψ Q Q φ l q φ l ψ q ψ Q Q φ h can decay promptly through a coupling (assuming the Z4 case) φ h φ 3 l y φ h q y φ h Q y φ l q y φ l Q

60 Other possible use of 2to3 σ 2 2 n σ 2 2 n σ γ σ 2 2 n m 2 m DM m DM m 1

61 E, p in a non-relativistic scattering the DM and nucleus have v 1 E k = 1 2 mv2 p = mv however, the relativistic scalar has E φ p φ, this requires p φ E φ <E χ k p χ,n φ carries away sizable energy but not much momentum! ( p N + p φ ) 4 ( p 2 N +2p φ p N ) 2 ( p N 2 +2 p φ p N ) 2 (2m N E R ) 2

62 Interaction strength Σ SI LUX CDMS Si XENON0 43 CDMSlite m 2 3 GeV

63 Cosmological Constraints : Neff γ γ The cross section is hard to estimate... assuming a quark loop with constituent quark mass, multiplied by a range of the form factor B 2 =1 0 φ decoupled from thermal bath at If the decoupling happens just before the BBN, Neff has a from the current measurement T freeze φ 2/3 Λ > MeV TeV 2 σ deviation Plank+WMAP+HighL This can be relaxed when having symmetry φ φ, χ e iπ/2 χ φ as a real scalar charged under a Z4

64 Constraints on the dark coupling χ χ χ χ χ χ Jonathan L. Feng, Manoj Kaplinghat, Huitzu Tu, and Hai-Bo Yu (09) Bullet cluster bound requires y χφ < 1 single light mediator and -0 GeV DM. when having a DM being a thermal relic requires y χ (m χ /GeV) 1/2

65 Collider bounds : LHC di-jet CMS 20/fb bound on the production rate requires M Q > 1.5 TeV mono-jet MG5+Pythia+PGS CMS 20/fb bound requires when M Q 1.5 TeV Λ > 6 TeV No significant bound yq yq monojet exclusion, CMS 20fb yq yq v MQ 2 TeV M Q TeV

66 Collider bounds : fixed target target detector p N φ N φ production rate geometrical suppression even with detection efficiency =1 Ep = 120 GeV number of the observed events << 1 No significant bound

67 Collider bounds : kaon decay φ φ Qq Λ can generate a tree-level decay of scalar mesons, or loop-induced decay through a flavor changing process K + π + φφ current experimental precision =0.03, Λ = TeV No significant bound

68 Bound on light sterile neutrino Planck+WMAP+H0+BAO+Xray cluster Mark Wyman, Douglas H. Rudd, R. Ali Vanderveld, and Wayne Hu (13)

69 Cosmological Constraints : 4He p/n in 4 He φ can in principle dissociated a 4He during the BBN time. However, the min recoil energy that a φ needs to kick out a nucleon from 4He is 7.1 MeV, which requires E φ > 125 MeV when the temperature is below MeV. =2E 2 φ/m4 He E max R Calculating the dissociation rate by including the Boltzmann distribution sets a bound Λ > 11 TeV when comparing the dissociation probability of 4He to the current precision

70 mφ 0.2 KeV DOTTED collaboration bounds WIMP to dmdm map SOLID exclusion from directly fitting dmdm to data Green Blue CL CDMS Si preferred region Red 90 CL upperbound from XENON0 Purple 90 CL upperbound from CDMSlite Magenta min y relic, where min 0 TeV from WD 6 TeV 4 yχ m DM GeV