Macro Dark Matter Experiments
Jagjit Singh Sidhu
Case Western Reserve University
Physics Department
Collaborators:
Glenn Starkman, Corbin Covault, Roshan Abraham, Robert Scherrer, Ralph
Harvey, Nathaniel Starkman Harrison Winch

DIMS Workshop
December 5th 2020

Macroscopic Dark Matter (Macros)

Macros are a dark matter candidate with characteristic mass
Mx in grams and cross section σx in cm2 .

Macroscopic Dark Matter (Macros)

Macros are a dark matter candidate with characteristic mass
Mx in grams and cross section σx in cm2 .
We take a phenomenological approach and look for signs ofmacros if they did constitute a reasonable fraction of the Dark
Matter.

Macro Paramater Space circa 2018
1025
1020

X [cm2]

1015

Atomic density
Nuclear density
Black holes

1010
105
10010 510 1010 15 110105

109

1013

1017

MX [g]

1021

1025

1029

Figure: Constraints on macro parameter space. Lack of microlensing
events in brown, Lack of bolides in green, CMB in grey, ancient mica inyellow, the continued existence of white dwarfs in blue, the period
between back-to-back superbursts from 4U-1820-30 in purple and lack ofpeculiar human deaths in red.

Probing parameter space

The mica results have determined a lower bound on
Mx,max ∝ nx Adetector d ∝ Adetector t. We need large detectors,
long integration times or both to probe higher masses.

Probing parameter space

The mica results have determined a lower bound on
Mx,max ∝ nx Adetector d ∝ Adetector t. We need large detectors,
long integration times or both to probe higher masses.
Macros impart energy either through hard sphere elastic
scatteringdEdE∼ ρσx vx2 ⇔∼ vx2dx
dmor through Coulomb interactions.

(1)

Probing parameter space

The mica results have determined a lower bound on
Mx,max ∝ nx Adetector d ∝ Adetector t. We need large detectors,
long integration times or both to probe higher masses.
Macros impart energy either through hard sphere elastic
scatteringdEdE∼ ρσx vx2 ⇔∼ vx2dx
dm
or through Coulomb interactions.

(1)

We must understand the relevant energy scales in the problem,
such as ionization energies, phase transition temperatures etc.

Fluorescence arXiv: 1808.06978

hopatgrees

30 degrees

acrofm30 dethpaofmoracto zenith

30 degrees

30 degrees

kmofm20thpaac
macro

Hypothetical Macro DM particle
detectable by modified Fluorescence
Detector (FD) of Pierre Auger Obs.

path of1 kmroFD

Figure: Conceptual diagram delineating the plausible detection of amacro dark matter particle by a modified version of a Fluorescence
Detector (FD) such as that of the Pierre Auger Observatory.

Fluorescence

A macro’s passage through the atmosphere forms a plasma.
For vx ≈ 250 kms−1 , kB T ∼ 10keV.

Fluorescence

A macro’s passage through the atmosphere forms a plasma.
For vx ≈ 250 kms−1 , kB T ∼ 10keV.
The ions then recombine to release photons that can bedetected using fluorescence detectors.

Fluorescence

A macro’s passage through the atmosphere forms a plasma.
For vx ≈ 250 kms−1 , kB T ∼ 10keV.
The ions then recombine to release photons that can bedetected using fluorescence detectors.
We calculated the luminosity produced by the passage of asingle macro as a function of σx .

Fluorescence

A macro’s passage through the atmosphere forms a plasma.
For vx ≈ 250 kms−1 , kB T ∼ 10keV.
The ions then recombine to release photons that can bedetected using fluorescence detectors.
We calculated the luminosity produced by the passage of asingle macro as a function of σx .
For two specific detectors, we then calculated the regions ofparameter space that could be probed.

Macro Paramater Space that Can be probed by Auger andJEM-EUSO
104

X [cm2]102
100

Auger One FD
Auger All FDs
JEM-EUSO
MicaCMB(DM-photon)

10 210 410 610 8 010101

102

103

104

MX [g]105106

107

Figure: Region of parameter space that can be explored by Auger andJEM-EUSO

FD time binning changes

Macros would move at 10−3 c, (c is the speed of ultra highenergy cosmic rays). We will require modifications to the timebinning mechanism. This is related to the time the object
takes to cross the field of view of a pixel.

FD time binning changes

Macros would move at 10−3 c, (c is the speed of ultra highenergy cosmic rays). We will require modifications to the timebinning mechanism. This is related to the time the object
takes to cross the field of view of a pixel.
Using the ADC on the Zedboard development kit, we havesuccessfully produced one pixel that is capable of detecting apassing macro. The next steps will include both scaling up
and chronologically tracking the trajectory of the macro.

Bolides arXiv:1908.00557

Constraints were placed on atomic density dark matter in 1986
from the null observation of bright fast moving meteorites.

Bolides arXiv:1908.00557

Constraints were placed on atomic density dark matter in 1986
from the null observation of bright fast moving meteorites.
From our work involving FDs we had understood this problem.

Bolides arXiv:1908.00557

Constraints were placed on atomic density dark matter in 1986
from the null observation of bright fast moving meteorites.
From our work involving FDs we had understood this problem.
We found that much denser objects of the same mass wereconstrained by this null result.

BolidesThe Desert Fireball Network is currently running and has
already constrained new parameter space because it’s muchlarger than the older network.

BolidesThe Desert Fireball Network is currently running and has
already constrained new parameter space because it’s muchlarger than the older network.
There are plans to expand the DFN as part of a global fireballnetwork over the coming years.

BolidesThe Desert Fireball Network is currently running and has
already constrained new parameter space because it’s muchlarger than the older network.
There are plans to expand the DFN as part of a global fireballnetwork over the coming years.
Assuming an expansion to 10 x the current area, and anobservation for roughly 10 x longer than has been currently
running, we estimate the parameter space that could beprobed.

Constraints from a lack of extrasolar bolides
105

X [cm2]

103

PCEDFNDFN futureMica
CMB (DM-Photon)

101
10 1
10 3
10 5
10 7 110103

105

MX [g]

107

109

Figure: Constraints from the older network that is no longer active, thecurrently running DFN and projections based on the expected final size ofthe DFN.

Straight Lightning

Figure: Schematic figure of ion channel formed by macro passage.

Straight Lightning

In most artificially triggered lightning experiments, a rocket
trailing a grounded triggering wire is launched when thequasi-static electric field at ground exceeds Ethreshold = 5 kV
m−1 .

Straight Lightning

In most artificially triggered lightning experiments, a rocket
trailing a grounded triggering wire is launched when thequasi-static electric field at ground exceeds Ethreshold = 5 kV
m−1 .
Macro induced plasma trail can mimic this behavior byforming channels for charge to move.

Straight Lightning

In most artificially triggered lightning experiments, a rocket
trailing a grounded triggering wire is launched when thequasi-static electric field at ground exceeds Ethreshold = 5 kV
m−1 .
Macro induced plasma trail can mimic this behavior byforming channels for charge to move.
These strikes would be very straight unlike any lightning everseen.

Low mass parameter space

Combined results
108

X [cm2]

105

Bolides
Bolides Projections
Fluorescence

102
10 1
10 4
WD

10 7
10 10 110103

105

MX [g]

107

109

Figure: Combined projections and constraints for low mass macros.

Low mass parameter space

Conclusions

Constraints have been produced and more probes have beensuggested to further tighten these constraints.

Low mass parameter space

Conclusions

Constraints have been produced and more probes have beensuggested to further tighten these constraints.
An interesting corollary to the bolide parameter spaceestimation of the future parameter space that could be probed
by the DFN is that on the scale of human lifetimes, it seems
unlikely that macro masses beyond ∼ 1010 g could be probedby any purpose built terrestrial detector.

Additional Material

Additional Material

Additional Material

Elastic vs. Inelastic Cross Sections

Figure: The microscopic cross-sections for the neutron reactions inuranium-238 at 600 K.