A t r i B h a t t a c h a r y a T a l k a t I - - PowerPoint PPT Presentation

SLIDE 1

D e t e c t i n g T e V

• P

e V s c a l e d a r k ma t t e r s i g n a t u r e s a t D e t e c t i n g T e V

• P

e V s c a l e d a r k ma t t e r s i g n a t u r e s a t t h e I c e C u b e n e u t r i n

• d

e t e c t

• r

t h e I c e C u b e n e u t r i n

• d

e t e c t

• r

D e t e c t i n g T e V

• P

e V s c a l e d a r k ma t t e r s i g n a t u r e s a t D e t e c t i n g T e V

• P

e V s c a l e d a r k ma t t e r s i g n a t u r e s a t t h e I c e C u b e n e u t r i n

• d

e t e c t

• r

t h e I c e C u b e n e u t r i n

• d

e t e c t

• r

A t r i B h a t t a c h a r y a

T a l k a t I n s t i t u t e O f P h y s i c s , B h u b a n e s wa r

4 A u g u s t 2 1 4

SLIDE 2

P l a n P l a n

Ul

t r a

• Hi

g h E n e r g i e s a n d t h e I c e C u b e n e u t r i n

• d

e t e c t

• r

–T

h e I C s e t u p , a i ms a n d

• b

j e c t i v e s

–R

e c e n t r e s u l t s a t I C

–I

s s u e s wi t h s t a n d a r d e x p l a n a t i

• n

s

Da

r k Ma t t e r d e c a y a n d n e u t r i n

• s

a t I C

Di

r e c t s e a r c h f

• r

h e a v y DM a t I C

Ge

n e r a l p r

• s

p e c t s f

• r

h e a v y DM s e a r c h e s

SLIDE 3

T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s

SLIDE 4

T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s

Probe highest energy neutrino production mechanisms Existence of tiny non-std physical effects (LV, etc.) Hunting for astrophysical point objects (AGN, etc.) using neutrinos Probe neutrino

• scillation at

highest energies Indirect search for very heavy DM decay DM annihilation at the galactic centre

SLIDE 5

T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s T h e n e u t r i n

• s

k y . . . t

• t

h e h i g h e s t e n e r g i e s

Probe highest energy neutrino production mechanisms Existence of tiny non-std physical effects (LV, etc.) Hunting for astrophysical point objects (AGN, etc.) using neutrinos Probe neutrino

• scillation at

highest energies Indirect search for very heavy DM decay DM annihilation at the galactic centre

SLIDE 6

N e u t r i n

• s

@ h i g h e s t e n e r g i e s : H

• w

C a t c h ' e m N e u t r i n

• s

@ h i g h e s t e n e r g i e s : H

• w

C a t c h ' e m

S

• l

u t i

• n

? K m3 D e t e c t

• r

s

K m3 d e t e c t

• r

s K m3 d e t e c t

• r

s

• Trap high fraction of incident neutrino fluxes
• Proper energy and direction (for tracks) reconstruction of large event

signature tracks

• Big enough to contain hadronic/em cascades
• Possibility of detection of double-bang signatures from incident ντ's

Ma i n i s s u e s wi t h d e t e c t i

• n
• E

x t r e me l y l

• w

i n c i d e n t fm u x e s

• Hu

g e i n c i d e n t e n e r g i e s – r e c

• n

s t r u c t i

• n

r e q u i r e s v

• l

u mi n

• u

s d e t e c t

• r

s

• F

l a v

• u

r d i s c r i mi n a t i

• n

?

SLIDE 7

Op

e r a t i

• n

a l s i n c e 2 1

–F

u l l e x p

• s

u r e s i n c e De c . 2 1 1

C

a p a b l e

• f

fm a v

• u

r d i s c r i mi n a t i

• n

–L

i mi t e d t

• d

e t e c t i

• n
• f

t h r e e d i s t i n c t e v e n t s i g n a t u r e s

E

x c e l l e n t e n e r g y r e c

• n

s t r u c t i

• n

–<

1 % f

• r

c

• n

t a i n e d c a s c a d e s

–~

3 % f

• r

t r a c k s wi t h c

• n

t a i n e d v e r t i c e s

Go

• d

d i r e c t i

• n

r e c

• n

s t r u c t i

• n

–U

p t

• 1

° f

• r

t r a c k s

–~

3 ° f

• r

c a s c a d e s

De

s i g n e d t

• r

u n ( mi n i ma l

• p

. c

• s

t ) f

• r

1 + y r s

2

8 UHE e v e n t s i n 6 6 2 d a y s

• f

r u n

• t

i me

–2

e v e n t s a t P e V + e n e r g i e s

–R

e c e n t l y r e p

• r

t e d 9 mo r e e v e n t s , ma k i n g t

• t

a l e v e n t n u mb e r 3 7

• v

e r 9 8 8 d a y s

P r e s e n t s e t u p f

• r

U H E d e t e c t i

• n

ν P r e s e n t s e t u p f

• r

U H E d e t e c t i

• n

ν

I c e C u b e

SLIDE 8

F l a v

• u

r @ I C F l a v

• u

r @ I C

Muon Track Cascades Double Bang

SLIDE 9

R e c

• n

s t r u c t i n g e v e n t s @ I c e C u b e R e c

• n

s t r u c t i n g e v e n t s @ I c e C u b e

Muon Tracks

Charged current interaction

• f the muon-neutrino

Clear tracks and excellent direction reconstruction Energy reconstruction is indirect – energy loss along track

Cascades

Charged current interaction

• f the electron-neutrino

and tau-neutrino Neutral current interactions of all flavours Excellent energy but poorer direction reconstruction

SLIDE 10

I n c i d e n t fm u x e s f r

• m

s t d . t h e

• r

y I n c i d e n t fm u x e s f r

• m

s t d . t h e

• r

y

Di

fg u s e fm u x f r

• m

a l l

• s

k y a s t r

• p

h y s i c a l s

• u

r c e s

–E

x p e c t e d t

• f
• l

l

• w

a p

• w

e r

• l

a w s p e c t r u m

• F

e r mi 1

s t

• r

d e r s h

• c

k s = 2 . → α

• No

r ma l i s a t i

• n

fj x e d b y

• b

s e r v a t i

• n

a l b e s t

• fj

t s –Ne

u t r i n

• s

i n s

• u

r c e s p r e d

• mi

n a n t l y f r

• m

p i

• n

d e c a y s

• S

t d .

• s

c i l l a t i

• n

i n c i d e n t fm a v

• u

r 1 : 1 : 1 a t e a r t h →

SLIDE 11

I n c i d e n t fm u x e s f r

• m

s t d . t h e

• r

y I n c i d e n t fm u x e s f r

• m

s t d . t h e

• r

y

Di

fg u s e fm u x f r

• m

a l l

• s

k y a s t r

• p

h y s i c a l s

• u

r c e s

–E

x p e c t e d t

• f
• l

l

• w

a p

• w

e r

• l

a w s p e c t r u m

• F

e r mi 1

s t

• r

d e r s h

• c

k s = 2 . → α

• No

r ma l i s a t i

• n

fj x e d b y

• b

s e r v a t i

• n

a l b e s t

• fj

t s –Ne

u t r i n

• s

i n s

• u

r c e s p r e d

• mi

n a n t l y f r

• m

p i

• n

d e c a y s

• S

t d .

• s

c i l l a t i

• n

i n c i d e n t fm a v

• u

r 1 : 1 : 1 a t e a r t h →

C

• s

mo g e n i c n e u t r i n

• s

( E 1 P e V ) ⩾

–C

• s

mi c r a y s i n t e r a c t i n g wi t h C MB R p h

• t
• n

s

SLIDE 12

O b s e r v a t i

• n

s @ I C [ 6 6 2 d a y s ] O b s e r v a t i

• n

s @ I C [ 6 6 2 d a y s ]

T

wo P e V + c a s c a d e s

–Hi

g h e s t e n e r g y n e u t r i n

• e

v e n t s e v e r

• b

s e r v e d

A

d d i t i

• n

a l 1 9 l

• w

e r e n e r g y c a s c a d e s

7

t r a c k e v e n t s

E

v e n t s f r

• m

4 s k y π

No

e v e n t f r

• m

3 T e V – 1 P e V

2 8 t

• t

a l e v e n t s

SLIDE 13

O b s e r v a t i

• n

s @ I C [ 6 6 2 d a y s ] O b s e r v a t i

• n

s @ I C [ 6 6 2 d a y s ]

B e s t

• fj

t l a r g e l y c

• n

s i s t e n t wi t h E

• 2

p

• w

e r fm u x u p t

• 1

. 1 P e V . . .

. . . B U T

➔ Unexplained sharp drop above

1 PeV

➔ Lack of events within

300 TeV – 1 PeV

➔ Sub-100 TeV energy event

numbers consistently higher than prediction from E-2 flux

At least 4.7 signal over atmospheric σ neutrino background with 90% c.l. charm estimates

SLIDE 14

U p d a t e d O b s e r v a t i

• n

s @ I C [ 9 8 8 d a y s ] U p d a t e d O b s e r v a t i

• n

s @ I C [ 9 8 8 d a y s ]

B e s t

• fj

t E

• 2

p

• w

e r fm u x n

• w

g i v e n b y

. . . A N D Y E T

➔ Unexplained sharp drop above

2.1 PeV

➔ Gap: 400 TeV – 1 PeV ➔ Sub-100 TeV event numbers

consistently higher than prediction from E-2 flux

At least 5.7 signal over atmospheric σ neutrino background with 90% c.l. charm estimates P l a u s i b l e a s t r

• e

x p l a n a t i

• n

SLIDE 15

I s s u e s w i t h u n i f

• r

m p

• w

e r

• l

a w e x p l a n a t i

• n

I s s u e s w i t h u n i f

• r

m p

• w

e r

• l

a w e x p l a n a t i

• n

Di

fg u s e n e u t r i n

• fm

u x f

• l

l

• w

s a u n i f

• r

m p

• w

e r l a w

Ga

p i n e v e n t s b e t w e e n 4 T e V t

• 1

P e V u n e x p l a i n e d

S

ma l l b u t n

• t

a b l e e x c e s s i n

• b

s e r v e d l

• w
• e

n e r g y e v e n t s ( ~ 1 T e V )

E

v e n t r a t e d r

• p

s t

• z

e r

• b

e y

• n

d 2 . 1 P e V

–

p r e d i c t s 3

• 6

e v e n t s f r

• m

3 —1 P e V

SLIDE 16

P r

• p
• s

i t i

• n

I P r

• p
• s

i t i

• n

I – D i f f u s e n e u t r i n

• fm

u x i n c i d e n t a t I C a s c

• mb

i n a t i

• n
• f

a s t r

• a

n d D M- d e c a y n e u t r i n

• s

SLIDE 17

D e c a y

• f

D a r k Ma t t e r D e c a y

• f

D a r k Ma t t e r

F

• r

n e u t r i n

• e

v e n t s i n I C r a n g e , n e e d DM s p e c i e s

• f

ma s s ≈ 1 T e V —2 P e V

–P

r

• b

a b l y n

• n
• t

h e r ma l i n n a t u r e

–He

a v i e r t h a n t h e t y p i c a l W I MP

S

l

• w

d e c a y s

• f

DM t

• S

t d . Mo d e l ( S M) p a r t i c l e s p

• s

s i b l e

–R

e l i c a b u n d a n c e r e q u i r e me n t s f

• r

c e

–F

u r t h e r c

• n

s t r a i n t s

• n

l i f e

• t

i me f r

• m
• b

s e r v a t i

• n

a l a s t r

• n
• my

T

w

• b
• d

y d e c a y s t

• v

a r i

• u

s S M c h a n n e l s p

• s

s i b l e

–C

h a r g e d l e p t

• n

p a i r s ( e

+

e

• ,

e t c . )

–Ne

u t r i n

• s

–Qu

a r k p a i r s ( u u , e t c . )

–Ga

u g e b

• s
• n

p a i r s ( W + W - , Z Z )

SLIDE 18

O b j e c t i v e : I C e v e n t s a s c

• mb

i n a t i

• n
• f

a s t r

• O

b j e c t i v e : I C e v e n t s a s c

• mb

i n a t i

• n
• f

a s t r

• a

n d D M- d e c a y n e u t r i n

• s

a n d D M- d e c a y n e u t r i n

• s

Ma

i n mo t i v a t i

• n

: E x p l a i n l

• w-

e n e r g y e x c e s s

R

e a s

• n

i n g

–S

e c

• n

d a r y n e u t r i n

• s

f r

• m

~ 1 T e V ma s s i v e DM d e c a y s t

• d

i fg e r e n t S M p r i ma r i e s a u g me n t d i fg u s e a s t r

• p

h y s i c a l n e u t r i n

• s

p e c t r u m

–T

h e a s t r

• fm

u x i t s e l f c a n b e t h e n s i g n i fj c a n t l y l

• w

e r , p r

• v

i d i n g a n a t u r a l e x p l a n a t i

• n

f

• r

t h e d e p l e t i

• n

i n e v e n t r a t e s b e y

• n

d 1 . 1 P e V

SLIDE 19

P r

• p

e r t i e s

• f

D M D e c a y P r

• p

e r t i e s

• f

D M D e c a y

A

s s u me s c a l a r DM

R

e s t r i c t t

• t

w

• b
• d

y d e c a y s

–S

i mp l i c i t y

–De

c a y s p e c t r u m w e l l

• k

n

• wn

( e . g . P Y T H I A 8 , P P P C , e t c . )

C

• n

s i d e r a l l p

• s

s i b l e S M c h a n n e l s :

–L

e p t

• n

p a i r s : e

+

e

• ,

μ

+

μ

• ,

τ+ τ-

–Ga

u g e b

• s
• n

p a i r s : W + W - , Z Z

–Qu

a r k p a i r s

SLIDE 20

S e c

• n

d a r y N e u t r i n

• S

p e c t r u m S e c

• n

d a r y N e u t r i n

• S

p e c t r u m

SLIDE 21

F l u x e s f r

• m

h e a v y D M d e c a y F l u x e s f r

• m

h e a v y D M d e c a y

Ga

l a c t i c

–

E

x t r a g a l a c t i c

–

C

• mp

a r a b l e c

• n

t r i b u t i

• n

s f r

• m

G a n d E G fm u x e s , fm u x

• b

t a i n e d f r

• m

4 s k y π

–Hi

g h e n e r g y n e u t r i n

• s

a t t e n u a t e d b y e a r t h ⇨ mo r e d

• wn

g

• i

n g n e u t r i n

• s

t h a n u p

• g
• i

n g

T

• t

a l F l u x = G a l a c t i c F l u x + E x t r a

• G

a l a c t i c F l u x

SLIDE 22

T

• t

a l D M + A s t r

• fm

u x a t I C T

• t

a l D M + A s t r

• fm

u x a t I C

 A

s s u me a s t r

• p

h y s i c a l fm u x t

• b

e u n b r

• k

e n p

• w

e r

• l

a w :

 T

• t

a l fm u x i n c i d e n t a t I C :

 B

e s t

• fj

t I C p

• w

e r

• l

a w :

SLIDE 23

D e t e r mi n i n g B e s t

• fj

t t

• O

b s e r v e d E v e n t s D e t e r mi n i n g B e s t

• fj

t t

• O

b s e r v e d E v e n t s

U

s e b i n

• b

y

• b

i n e v e n t r a t e s

• b

s e r v e d a t I C

De

t e r mi n e t

• t

a l i n c i d e n t fm u x b y v a r y i n g p a r a me t e r s :

C

• mp

a r e wi t h p r e d i c t e d e v e n t r a t e s f r

• m

t

• t

a l i n c i d e n t fm u x b y e v a l u a t i n g t

• t

a l ² χ

–L

• w

e r ² / d .

• .

f i n d i c a t e s b e t t e r fj t χ

U

s e I C b e s t

• fj

t a s n u l l

• s

t a t i s t i c t

• d

e t e r mi n e g

• d

n e s s

• f

fj t f r

• m

mo d e l fm u x b y F

• t

e s t

SLIDE 24

B e s t

• fj

t s a n d g

• d

n e s s

• f
• fj

t B e s t

• fj

t s a n d g

• d

n e s s

• f
• fj

t

SLIDE 25

B e s t

• fj

t s a n d g

• d

n e s s

• f
• fj

t B e s t

• fj

t s a n d g

• d

n e s s

• f
• fj

t

The low values of the p-value indicate that the fit to the data in the DM + Astro model with a reduced astrophysical flux improves upon the IC best-fit significantly. Conventionally, p <= 0.05 indicates strong presumption against the null hypothesis, which in this case refers to the hypothesis that the fit does not improve statistically significantly.

SLIDE 26

“ “ H i d d e n ” c

• mp
• n

e n t : ν H i d d e n ” c

• mp
• n

e n t : ν f

r

• m

f r

• m

D M d e c a y ? D M d e c a y ?

χ² = 4.209 p-value = 0.061 χ² = 4.188 p-value = 0.060 χ² = 4.209 p-value = 0.061 χ² = 4.445 p-value = 0.072

C

• mp

a r e w i t h I C b e s t

• fi

t

² χ I

C

= 1 . 7

SLIDE 27

I C e v e n t s a s n e u t r i n

• s

f r

• m

D M + A s t r

• I

C e v e n t s a s n e u t r i n

• s

f r

• m

D M + A s t r

• MOR

E DA T A R E QUI R E D

W i

t h i n t h e p u r v i e w

• f

l i mi t e d s t a t i s t i c s , r e d u c e d a s t r

• p

h y s i c a l fm u x + l

• w

e n e r g y n e u t r i n

• s

f r

• m

DM d e c a y fj t s

• b

s e r v e d d a t a s i g n i fj c a n t l y b e t t e r t h a n t h e I C b e s t

• fj

t wi t h a p

• w

e r

• l

a w a s t r

• p

h y s i c a l fm u x a l

• n

e

–C

• n

s i s t e n c y wi t h l a c k

• f

e v e n t s i n t h e “ w e l l ”

–B

e t t e r ma t c h t

• t

h e s u b

• 1

T e V e v e n t s

E

v e n t s p e c t r u m f a v

• u

r s T e V s c a l e DM, a n d a s t r

• E
• 2

fm u x a t r

• u

g h l y h a l f t h a t

• f

I C 6 6 2

• d

a y b e s t

• fj

t .

SLIDE 28

P r

• p
• s

i t i

• n

I I P r

• p
• s

i t i

• n

I I – – P e V e v e n t s f r

• m

s c a t t e r i n g

• f

r e l a t i v i s t i c D M a g a i n s t i c e

• n

u c l e

• n

SLIDE 29

Mo t i v a t i

• n

a n d Mo d e l Mo t i v a t i

• n

a n d Mo d e l

Ma

i n mo t i v a t i

• n

: E x p l a i n P e V e v e n t s a n d c u t

• f

Hy

p

• t

h e s i s e e x i s t e n c e

• f

a t w

• c
• mp
• n

e n t DM s e c t

• r

–V

e r y h e a v y s c a l a r DM s p e c i e s (, P DM) , m φ

φ

~ 5 P e V

• No

n

• t

h e r ma l i n

• r

i g i n

• F

r

• z

e n

• u

t

• f

i n t e r a c t i

• n

s wi t h S M p a r t i c l e s c

• mp

l e t e l y

• On

l y d e c a y s t

• a

l i g h t e r DM wi t h i n t h e s e c t

• r

–L

i g h t e r DM s p e c i e s (, T DM) , m χ

χ

( ~ T e V ) ≪ mφ

• S

t a b l e , F e r mi

• n

i c

• P

r e d

• mi

n a n t l y p r

• d

u c e d v i a t w

• b
• d

y d e c a y

• f

P DM: φ → χχ

• We

a k i n t e r a c t i

• n

s wi t h n u c l e i me d i a t e d b y h e a v y ( B S M) n e u t r a l g a u g e b

• s
• n

Z '

SLIDE 30

P r

• p

e r t i e s

• f

D M s p e c i e s P r

• p

e r t i e s

• f

D M s p e c i e s

P

DM

–L

a r g e d e c a y l i f e t i me , > 1 τ

2

s

–Ma

k e s u p a l mo s t e n t i r e r e l i c a b u n d a n c e

• f

u n i v e r s e

T

DM

–P

r

• d

u c e d mo n

• c

h r

• ma

t i c a l l y , e n e r g y

• f

m φ/ 2

–Ne

u t r a l c u r r e n t i n t e r a c t i

• n

wi t h n u c l e i , me d i a t e d b y Z '

• A

n a l

• g
• u

s t

• N

n e u t r a l c u r r e n t i n t e r a c t i

• n

ν

–Do

e s n

• t

c

• n

t r i b u t e t

• c
• mo

v i n g DM, e . g . g a l a x y r

• t

a t i

• n

c u r v e s , e t c .

SLIDE 31

C r

• s

s

• s

e c t i

• n

a n d A v g . y C r

• s

s

• s

e c t i

• n

a n d A v g . y

A s s u me a r b i t r a r y n

• r

ma l i s a t i

• n

G ² = . 5

SLIDE 32

D M P a r a me t e r s F i x e d b y O b s e r v a t i

• n

s D M P a r a me t e r s F i x e d b y O b s e r v a t i

• n

s

P

DM ma s s d e t e r mi n e d b y h i g h

• e

n e r g y c u t

• f

–R

e q u i r e s e v e n t r a t e s p e a k i n g a t ~ 1 . 1 P e V , t h e r e f

• r

e p e a k T DM fm u x a t

–F

i x e s P DM ma s s a t 2 E

p e a k

= 5 . 6 P e V

No

r ma l i s a t i

• n

d e t e r mi n e d b y n u mb e r

• f

P e V + e v e n t s

–

i mp l i e s , e v e n t r a t e a t I C

F i x τφ = 1

2 4

s , G ² = . 4 5

3 P e V + e v e n t s i n 9 8 8

• d

a y d a t a

SLIDE 33

T h e S u b

• P

e V E v e n t S p e c t r u m T h e S u b

• P

e V E v e n t S p e c t r u m

• S

t e e p l y f a l l i n g E

• 3

s p e c t r u m e x p l a i n s s u b

• P

e V e v e n t s

• S
• u

r c e

• f

n e u t r i n

• s

: e x t r a

• g

a l a c t i c

• b

j e c t s l i k e GR B ' s , A GN' s , e t c .

• C
• n

s i s t e n t w i t h 4 —1 T e V “ g a p ”

• S
• fu

e r fm u x n a t u r a l l y d r

• p

s b e l

• w

t h r e s h

• l

d a b

• v

e P e V ' s

SLIDE 34

P u t t i n g t h e t wo t

• g

e t h e r P u t t i n g t h e t wo t

• g

e t h e r

T h e F u l l E v e n t S p e c t r u m T h e F u l l E v e n t S p e c t r u m

P

e V + e v e n t s e x c l u s i v e l y f r

• m

T DM s c a t t e r i n g

• n

i c e

• n

u c l e u s wi t h i n I C

–S

• fu

a s t r

• p

h y s i c a l n e u t r i n

• s

p e c t r u m e n s u r e s n

• c
• n

t r i b u t i

• n

a t P e V +

Ha

r d

• c

u t

• fg

a t 2 . 5 P e V e x p e c t e d

–Ma

x e n e r g y s e t b y P DM ma s s

S

• fu

E

• 3

d i fg u s e a s t r

• p

h y s i c a l fm u x s p e c t r u m e n s u r e s c

• mp

a t i b i l i t y wi t h 2 —4 T e V e v e n t r a t e s

–A

l s

• e

x p l a i n s g a p f r

• m

4 —1 T e V

SLIDE 35

P r

• b

a b l e T e l l

• t

a l e S i g n a t u r e s P r

• b

a b l e T e l l

• t

a l e S i g n a t u r e s

. . .

• r

d e fj n i t e f a l s i fj a b i l i t y ? . . .

• r

d e fj n i t e f a l s i fj a b i l i t y ?

I

C e x p e c t s t

• r

u n f

• r

t h e n e x t d e c a d e

–E

v e n t r a t e s

• f

a b

• u

t 1 y r

• 1

W i

t h s t a t i s t i c a l l y s i g n i fj c a n t d a t a ( s a y , 5 y r s ) , i f

–C

• mp

l e t e l a c k

• f

e v e n t s p e r s i s t s a b

• v

e s

• me

P e V + t h r e s h

• l

d

• De

fj n i t e p

• i

n t e r t

• a

h a r d c u t

• f

, DM- l i k e ?

–Ga

p b e t w e e n 4 —1 T e V p e r s i s t s

• P
• w

e r

• l

a w fm u x c a n n

• t

e x p l a i n

• P

r

• b

a b l y p

• i

n t s t

• t

wo d i f e r e n t c

• mp
• n

e n t s i n t h e n e u t r i n

• fm

u x

–S

• me

g a l a c t i c b i a s e x p e c t e d i n P e V + e v e n t s

• P

u r e a s t r

• fm

u x w

• u

l d b e s t r

• n

g l y i s

• t

r

• p

i c

SLIDE 36

G e n e r a l i s a t i

• n

& S i d e

• e

f f e c t s G e n e r a l i s a t i

• n

& S i d e

• e

f f e c t s

Di

fg e r e n t i n t e r a c t i

• n

s f

• r

d i fg e r e n t n a t u r e s

• f

T DM

–S

c a l a r

• r

f e r mi

• n

i c ?

–A

d d i t i

• n

a l s y mme t r i e s ?

P

r

• s

p e c t i v e me t h

• d

t

• d

i s c

• v

e r e x i s t e n c e

• f

u l t r a

• f

a s t DM i n n e x t

• g

e n n e u t r i n

• t

e l e s c

• p

e s

–C

• mp

l e me n t a r y t

• DM

d i r e c t s e a r c h e s s e n s i t i v e t

• l
• w

e r e n e r g y DM

–P

r

• b

a b l y

• n

l y c u r r e n t l y v i a b l e w a y t

• l
• k

f

• r

f a s t ( n

• n
• c
• mo

v i n g ) DM

T

DM c

• n

t r i b u t e s a d d i t i

• n

a l l i g h t d e g r e e s

• f

f r e e d

• m

i n t h e e a r l y u n i v e r s e

–N

r e l

f r

• m

P L A NC K ( 3 . 3 4 ± . 3 2 ) v s N

e f

f r

• m

S M ( 3 . 4 )

SLIDE 37

C

• n

c l u s i

• n

s

SLIDE 38

C

• n

c l u s i

• n

s C

• n

c l u s i

• n

s

I

C e v e n t s a wi n d

• w

t

• i

n t e r e s t i n g p

• s

s i b i l i t i e s

MOR

E DA T A R E QUI R E D P r e s e n t e v e n t r a t e s ( 3 7

• v

e r 9 8 8 d a y s ) t

• l
• w

P

• s

s i b i l i t y

• f

b e i n g e x p l a i n e d b y s t d . a s t r

• p

h y s i c a l p h e n

• me

n a . . .

.

. . b u t t a n t a l i s i n g h i n t s

• f

n

• n
• c
• n

f

• r

mi t y

I

f n

• n
• s

t d . f e a t u r e s p e r s i s t , wi l l c a l l f

• r

i n n

• v

a t i v e s u g g e s t i

• n

s f

• r

e x p l a n a t i

• n

s

P

• s

s i b i l i t y

• f

fm u x c

• mi

n g f r

• m

d i s p a r a t e s

• u

r c e s

–DM-

d e c a y c

• n

t r i b u t i n g

• n

e c

• mp
• n

e n t

–A

s t r

• p

h y s i c a l s

• u

r c e s t h e

• t

h e r