“Promises” of HE Neutrinos
David Eichler
The “dovecote” for HEN Theorists
(circa 1979)
target
HE ion source
SN Remnants
AGN, etc.
Neutron Stars
Microquasars
Winds
GRB
(not yet
understood)
Binary
Dense
SN ejecta companion
clouds
Accretion
column,
jet
Winds
Has anything changed?
Has anything changed?
Young neutron stars in dense supernova ejecta
are now called “failed GRB”.
Has anything changed?
Shock acceleration dependability, efficiency generally accepted
now, (though relativistic shocks may be less efficient, could be a major
problem)
Has anything changed?
Shock acceleration dependability, efficiency generally accepted
now, (though relativistic shocks may be less efficient, could be a major
problem)
Note: spectrum goes as E-(2+p), so UHE energy flux for 1014eV^ (1020 eV)
primaries goes as 10-5p (10-11p).
Has anything changed?
Shock acceleration dependability, efficiency generally accepted
now, (though relativistic shocks may be less efficient, could be a major
problem)
Collapsed star engines apparently blow out baryons (GRB afterglow)
Has anything changed?
Shock acceleration dependability, efficiency generally accepted
now, (though relativistic shocks may be less efficient, could be a major
problem)
Collapsed star engines apparently blow out baryons (GRB afterglow)
AGN detected [EGRET] to put out L =1048 erg/s or more in
EM
HE emission. [You can never limit Ltotal, because much of
output of central engine could be unobservable (e.g. baryon
kinetic energy), or transient.]
Has anything changed?
Shock acceleration dependability, efficiency generally accepted
now, (though relativistic shocks may be less efficient, could be a major
problem)
Collapsed star engines apparently blow out baryons (GRB afterglow)
AGN detected [EGRET] to put out 1048 erg/s or more in HE
emission
UHE gamma ray astronomy providing good sanity check for
energy budgets, acceleration efficiency
The Bad News for GRB Neutrinos:
They have lower fluences than AGN
Eichler 1994
There was, of course, bad nus
on occasion, (Lande 1974,
Cygnets, GZK cutoff violation…..).
The Good News for GRB:
The bad news was a generation ago
The Good News for GRB:
The bad news was a generation ago
GRB teach us that baryons, outflow, particle acceleration
can be generated by collapsed stellar remnants
The Good News for GRB:
The bad news was a generation ago
GRB teach us that baryons, outflow, particle acceleration
can be generated by collapsed stellar remnants
We don’t see most GRB! Probably ~99.9% go unseen. So
maybe the neutrinos will come from the other 99.9%
Why?
For a given energy output,
Vmax = Rmax3ΔΩ α Ω-1/2
is enhanced by collimation.
If the universe were bigger, detected GRB would be,
on average, even more collimated.
But…there may be a “quiet majority” of less
collimated GRB or radiation fields from
them that are much closer, and more relevant
to HE neutrinos and gravitational waves.
Because collimation enhances detectability, it overrepresents highly
collimated, distant radiation.
Various types of uncollimated radiation –
scattered photons,
kinematically softened photons at large viewing angles,
gravitational waves,
neutrinos
may coincide with each other more often. Nearby events from the “quiet
majority” may be waiting for us in coincidence from the relatively
uncollimated forms of radiation.
Scattered photons from GRB?
GRB 980425 (SN 1998bw)
GRB 060218
Smooth light curves, proximity, deviation from the
Amati relation, all consistent with scattering off
“slow” baryons.
Hard to soft evolution of light curve consistent
with acceleration of scatterer
Scattering increases
solid angle, favors
nearby sources
Lorentz
transformation
Scattering increases
solid angle, favors
nearby sources
Lorentz
transformation
Anything with a back edge,
(ejecta, plowed up wind material,
pair fireball)
Obs
Scattering increases
solid angle, favors
nearby sources
scattering
Scatterring always raises source above and/or to left Eichler and Mandal ‘09
Smooth light curves evidence for a
light echo.
GRB
980425
Smothered GRB
(DE and Levinson 1999)
If GRB 980435 scattered off x optical depths of
scattering material, then there should be a lot
more with different optical depth . For x>>10,
GRB might be smothered, but you might detect
neutrinos and possibly other stuff, e.g.
adiabatically decelerated gamma rays (now
known as dirty fireballs).
Smothering direction dependent, more general
than “failed” GRB, which are very smothered.
GRB
060218
GB 060218 explained as scattering off accelerating screen
Mandal and DE ‘09
Not the GRB.
Adiabatically
cooled
gamma rays,
or breakout
flash?
Short hard GRB [SHB]
Wider viewable angle + acceleration by
radiation pressure consistent with absence of giant envelope, galaxy type
closer distances
shorter duration
harder spectra
long, soft tails
Accelerating
fireball
Accelerating
fireball
Neutrinos?
GW?
So short GRB may have wider cone
of detection that longer ones. But,
X-ray tails of short bursts may have
even wider cones of detection.
Long GRB Failure?
Most collapsars do not have
magnetic fields of 1015 G. Energy
release may be much slower, so
central engine may fail to punch
hole in host envelope.
Failed GRB may be much more
frequent than successful ones (DE and
Levinson ’99).
Conclusions
Gravitational waves, neutrinos, scattered gamma
rays, and possibly X-ray tails more likely to
coincide with each other than with (even) short
GRB.
New concepts in wide angle X-ray cameras
welcome (for X-ray tails, dirty fireballs, breakout
flashes)
Most promising HE GRB neutrino sources may be
smothered or failed GRB
Conclusions
Good luck to the brave experimentalists.
You deserve it.
Top down neutrino production
(Levinson and Eichler 2004)
Sprinkle B field line-crossing neutrons into a
pure Poynting flow, high G:
Wait for one to decay, get collisional avalanche
with observer frame energy of G2.
Most burst energy radiated as neutrinos