Solar Neutrinos as a Probe of Dark Matter-Neutrino Interactions

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1 Solar Neutrinos as a Probe of Dark Matter-Neutrino Interactions based on arxiv: , with I. Shoemaker and L. Vecchi FRANCESCO CAPOZZI

2 Model Dark Matter nx Standard Model U(1) s Sterile Sector Francesco Capozzi - The Ohio State University

3 Motivation: SBL anomalies and νs Almost all data from neutrino oscillation can be explained in a 3ν framework. There are however a few anomalies observed at very short baseline: LSND anomaly GALLIUM anomaly Δm SBL ~ 1 ev REACTOR anomaly sin θ ~ 0.01 Francesco Capozzi - The Ohio State University 3

4 Motivation: νs secret interactions νs secret interactions may reconcile SBL anomalies with Cosmology - K. S. Babu and I. Z. Rothstein, Phys.Lett. B75 (199) S. Hannestad, R. S. Hansen and T. Tram, Phys. Rev. Lett. 11 (014) B. Dasgupta and J. Kopp, Phys. Rev. Lett. 11 (014) A. Mirizzi, G. Mangano, O. Pisanti and N. Saviano, Phys. Rev. D91 (015) J. F. Cherry, A. Friedland and I. M. Shoemaker, X. Chu, B. Dasgupta and J. Kopp, JCAP 15 (015) J. F. Cherry, A. Friedland and I. M. Shoemaker, L. Vecchi, Phys. Rev. D94 (016) ν - DM interaction may solve the missing satellite problem - D. Hooper, M. Kaplinghat, L. E. Strigari and K. M. Zurek,, Phys. Rev. D76 (007) L. G. van den Aarssen, T. Bringmann and C. Pfrommer, Phys.Rev.Lett. 9 (01) I. M. Shoemaker, Phys.Dark Univ. (013) B. Bertoni, S. Ipek, D. McKeen and A. E. Nelson, JHEP 04 (015) T. Binder, L. Covi, A. Kamada, H. Murayama, T. Takahashi and N. Yoshida, Francesco Capozzi - The Ohio State University 4

5 Constraints Possibility that active-sterile oscillations turned on after CMB: no constraint from BBN or CMB. (L. Vecchi Phys. Rev. D 94 (016) no.11, ) UHEν interaction with CNB converts νa to νs, depleting νa from distant sources: constraints from the isotropy observed by IceCube events. (J. F. Cherry, A. Friedland and I. Shoemaker, arxiv: ) ν-dm interaction introduces a cutoff in the matter power spectrum: contraints from Lyman-α (Mcut < 5 x M ). (L.G.van den Aarssen, T.Bringmann and C.Pfrommer, Phys. Rev. Lett. 9 (01) 31301, D.Hooper, M.Kaplinghat, L.E.Strigari and K.M.Zurek, Phys. Rev. D 76 (007) 3515) DM-DM interaction modifies halo ellipticity, cluster mergers, as well as the mass profile of dwarf galaxies. ( P. Agrawal, F. Y. Cyr-Racine, L. Randall and J. Scholtz, arxiv: ) Francesco Capozzi - The Ohio State University 5

6 Constraints mx = 5 GeV Solar Dark MSW (this work) IceCube SN1987A Lyman DM halo ellipticity Francesco Capozzi - The Ohio State University 6

DM-νs interaction creates a new matter potential which alters the

7 Possible signature: solar neutrinos = DM particle = DM-nucleon interaction = νe DM clusters in the core of the Sun. DM-νs interaction creates a new matter potential which alters the expected number of νe observed on Earth. Francesco Capozzi - The Ohio State University 7

8 DM in the Sun Neglecting DM annihilation (asymmetric DM), evaporation (MX>4 GeV), and selfinteractions, the equation describing DM clustering in the Sun is NX(t) = C t: ( A. Gould, Astrophys.J. 31 (1987) 571) N X /N e 1 nx 45 cm for spin-independent cross-section After thermalization: n X (r) = N X rx 3 e r /r X 3/ r X (r) = s r 3T 5GeV 0.05 R G N m X m X Francesco Capozzi - The Ohio State University 8

9 DM in the Sun ρ( ) 0 15 DM, mx = 15 GeV DM, mx = 5 GeV / Francesco Capozzi - The Ohio State University 9

10 New matter potential The coherent scattering of active neutrinos, via oscillations into νs, is affected by DM. In the limit of zero average velocity of the DM: hx µ µ0 Xi = n X and V e = s X g + m A n X. If m A > 14 ev p m X /5 GeV the gradient of nx can be neglected (contact interaction) V e ' G X n X = p G F n e (0)e r /r X G X = s X g A m A G Xn X (0) p GF n e (0) In this range of ma, we can have GX >> GF in order to compensate small nx (ξ > 1) Francesco Capozzi - The Ohio State University

11 Neutrino oscillations: analytic approach Assuming sin θi4 Vs < Δm 31, we have: P ee,day = c 4 13c (1 + cos 1 cos m ) +s 4 13c s O(s i4v s E/ m 31) cos m = cos 1 V p x sin 1 + V y +( cos 1 V x ) Francesco Capozzi - The Ohio State University 11

12 Constraints from solar neutrinos We consider data on 8 B (SNO only), 7 Be and pep neutrinos. pp neutrinos are almost unaffected by Vs. mx is fixed to 5 GeV. s = 0.07 s = s = ξ>0, marginalized m = 1.6 ev δ = 0.0 ξ > 0 13,14,34 s = 0.07 s = s = ξ<0, marginalized m = 1.6 ev δ = 0.0 ξ < 0 13,14,34 ev 5 1 ev 5 m 1 1 m sin θ sin θ 1 Presence of a Dark-LMA solution (θ1>π/4), as obtained by non-standard interactions (NSI) Francesco Capozzi - The Ohio State University 1

13 Constraints from solar neutrinos We vary θ14 and ξ, while θ4 = θ34 = 0. Solar parameters (Δm 1,θ1) held fixed to current global best fit. 1 s = 0.0 s = m = 1.6 ev δ = 0.0 ξ > 0 13,14,34 1 s = 0.0 s = m = 1.6 ev δ = 0.0 ξ < 0 13,14,34 ξ>0 ξ<0 1 1 sin sin θ 14 θ ξ ξ Too large θ14 suppresses Pee. ξ sin θ14 < O() Francesco Capozzi - The Ohio State University 13

14 Constraints from solar neutrinos We vary θ14 and ξ, θ4 is fixed at SBL anomaly, while θ34 = 0. Solar parameters (Δm 1,θ1) held fixed to current global best fit. 1 s = s = m = 1.6 ev δ = 0.0 ξ > 0 13,14,34 1 s = s = m = 1.6 ev δ = 0.0 ξ < 0 13,14,34 ξ>0 ξ<0 1 1 sin sin θ 14 θ ξ ξ For large ξ there are regions of the parameter space where Pee change abruptly Francesco Capozzi - The Ohio State University 14

15 Constraints from solar neutrinos 0.8 Z P i i(e) i (r) P ee (E) = dr P ee,day (r, E) P i(e) i 0.6 P ee 0.4 SM (ξ (ξ, sin θ 14 ) = (70, 0.03), sin θ 14 ) = (-300, 0.004) E [MeV] Francesco Capozzi - The Ohio State University 15

16 Conclusions - The Sun might be a probe of neutrino-dm interactions - For sufficiently light exotic sectors, GX/GF can be extremely large and compensate the possibly small density of the DM - It is mostly the physics of 8 B, 7 Be, and CNO neutrinos that is modified - ξ sin θ14 < O() - Similarly to NSI, a Dark-LMA solution is mildly favored for ξ < 0 - Our framework generalizes the more conventional neutrino-nsi Francesco Capozzi - The Ohio State University 16

17 Thank you Francesco Capozzi - The Ohio State University

18 Backup Francesco Capozzi - The Ohio State University

19 Model Lagrangian Dark Matter nx Standard Model N = SM singlet νs = non sterile fermions coupling to U(1) gauge field A U(1) s φ = dark scalar with U(1) charge conjugate to νs Sterile Sector X = dark matter particle L s i@ s + g A A 0 µj µ + y s N s + y a NHL+ m N NNc +hc. J µ = s s µ s + X X µ X We assume φ acquires a vacuum expectation value which generates a mass mα for Α μ, as well as a N, νs mixing. Electroweak symmetry breaking the second line induces a mixing between active neutrinos and N. sin min(y a hhi/y s h i,y s h i/y a hhi) Francesco Capozzi - The Ohio State University 19

20 Constraints UHEν interaction with CNB converts νa to νs: observed by IceCube events. (J. F. Cherry, A. Friedland and I. Shoemaker, arxiv: ) constraints from the isotropy The MFP of high-energy neutrinos as they scatter on the CNB cannot be too short, as most of the flux originating at cosmological distances would not reach us. Even if one boosts the flux emitted by the nearby sources by a large factor, the observed flux would look highly anisotropic J. F. Cherry, A. Friedland and I. M. Shoemaker, Francesco Capozzi - The Ohio State University 0

21 Constraints νs-dm or DM-DM interaction introduces a cutoff in the matter power spectrum: contraints from Lyman-α (Mcut < 5 x M ). (L.G.van den Aarssen, T.Bringmann and C.Pfrommer, Phys. Rev. Lett. 9 (01) 31301, D.Hooper, M.Kaplinghat, L.E.Strigari and K.M.Zurek, Phys. Rev. D 76 (007) 3515) Structure cannot grow as long as the momentum-transfer rate exceeds the Hubble rate. We compute the momentum-transfer rate via (T )= X i g i 6m X T Z 1 0 d 3 p ( ) 3 f p i(1 ± f i ) p p + m i Z 0 4p dt( t) d X+i!X+i dt T. Binder, L. Covi, A. Kamada, H. Murayama, T. Takahashi and N. Yoshida, The kinetic decoupling temperature is obtained by solving when the momentum transfer rate drops below the Hubble rate: (T KD )=H(T KD ) The mass of the largest gravitationally bound objects (i.e. the proto-halos) that can form causally is dictated by the mass enclosed in a Hubble volume at TKD. We require M < M(Lyman-α)=5x M, which corresponds to TKD > 0.15 KeV. Francesco Capozzi - The Ohio State University 1

22 Neutrino oscillations H = 1 E U 0 0 m 1 m 31 1 C A U + 0 V CC C A, V s = V e V NC m 41 V s V e = p G F n e (0)e r /r X G Xn X (0) p GF n e (0) U = R 34 R 4 R14 R 3 R13 R 1 Francesco Capozzi - The Ohio State University

23 Numerical analysis details (p) = SNO(p)+ Be7(p)+ pep(p) Z hp i ee(p,e)i dr i (r)p ee (p,r,e) Be7(p) = hp 7 Be ee (p, 86 kev)i ! pep(p) = hp pep ee (p, 1440 kev)i , Francesco Capozzi - The Ohio State University 3

24 Numerical analysis details hp i ee(p,e)i Z SNO(p) =min (p) = SNO(p)+ Be7(p)+ pep(p) dr i (r)p ee (p,r,e) A(p,E)= hp 8 B ee,night (p,e)i 8 < : 5X i,j=0 ai (p) hp SNO a SNO i 1 ij ee (p,e)i = hp 8 B ee (p,e)i 1 hp 8 B es (p,e)i hp 8 B ee,day (p,e)i hp 8 B ee,night (p,e)i + hp 8 B ee,day (p,e)i. aj (p) a1, a, a3 derive from a quadratic fit of Pee(day). a4, a5, derive from a linear fit of A. a0 is the total 8 B flux Φ. Σ is a correlation matrix given by the SNO collaboration a SNO j 9 = + SSM ( ) ; Francesco Capozzi - The Ohio State University 4

25 Neutrino oscillations: analytic approach Assuming sin θi4 Vs < Δm 31, we have: P ee,day = c 4 13c (1 + cos 1 cos m )+s 4 13c s O(s i4v s E/ m 31) cos m = cos 1 V p x sin 1 + V y +( cos 1 V x ) V x = 1 VCC c 13c 14 + V s A B V y = V s AB A = e i 14 c 13 c 4 c 34 s 14 e i 13 s 13 c 34 s 3 s 4 + e i 34 c 3 s 34 B = c 3 c 34 s 4 e i 34 s 3 s 34 Francesco Capozzi - The Ohio State University 5

26 Constraints from solar neutrinos 1 s = 0.07 s = m = 1.6 ev δ = 0.0 ξ < 0 13,14,34 1 s = 0.07 s = m = 1.6 ev δ = 0.0 ξ > 0 13,14, sin sin θ 34 θ ξ ξ Francesco Capozzi - The Ohio State University 6

27 Comparison with NSI H NSI = p G F N e (r) A + p G F X f=e,u,d N f (r) 0 f ee f eµ f 1 f eµ f µµ f A µ f e f µ f In our model, in the limit sinθ >0 and sinθ ξ held fixed, oscillations are described by the standard 3x3 Hamiltonian, plus: H new ij = V s (R 34 R 4 R 14 ) 4i(R 34 R 4 R 14 ) 4j! p G F n e (0)e r /r X i4 j4 The potential Hnew has the same appearance of NSI, provided we identify p GF n e (0)e r /r X i4 j4 = V CC " ij Francesco Capozzi - The Ohio State University 7

28 Constraints from solar neutrinos 0.8 Z P i i(e) i (r) P ee (E) = dr P ee,day (r, E) P i(e) i P ee 0.6 P ee cos 1 sin 1 + V y cos 1 V x 0.4 SM (ξ (ξ, sin θ 34 ) = (300, 0.07), sin θ 34 ) = (-1300, 0.1) E [MeV] Francesco Capozzi - The Ohio State University 8

How to make the short baseline sterile neutrino compatible with cosmology

How to make the short baseline sterile neutrino compatible with cosmology a, Maria Archidiacono b, Steen Hannestad c and Thomas Tram d a Max-Planck-Institut für Kernphysik Saupfercheckweg 1, 69118 Heidelberg,