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The Diffused Polarized ALPs (Axion-like Particles) Power Spectrum in the�Microwave Sky

Harsh Mehta

Department of Astronomy & Astrophysics, TIFR

Mumbai, India

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Harsh Mehta

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02-08-2024

CMB-S4 Summer Collaboration Meeting

2nd August, 2024

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arXiv:2405.08879 (Published in JCAP)

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Harsh Mehta

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02-08-2024

Nasa.gov

www.researchgate.net

Planck | IPAC (caltech.edu)

 

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CMB photon-ALP resonant conversion

 

Harsh Mehta

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02-08-2024

Nasa/CXC/Univ of Missouri/M.Bradwin et al.

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Background signal from Unresolved Galaxy clusters

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Harsh Mehta

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02-08-2024

ALP distortion signal

Galaxy clusters

Dark Matter Halos

Matter density field

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Harsh Mehta

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02-08-2024

Mehta and Mukherjee, A Diffused Background from Axion-like Particles in the Microwave Sky, 2024 arXiv:2405.08879

Mehta and Mukherjee, A power spectrum approach to the search for Axion-like Particles from resolved galaxy clusters using CMB as a backlight, 2024�arXiv:2405.08878

CMB + ALP

CMB only

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The ALP diffused Background

Harsh Mehta

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02-08-2024

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The CMB power spectrum

 

Harsh Mehta

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02-08-2024

Nasa.gov

(Foregrounds using PySM)

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Halo Modelling of the ALP distortion signal�

Harsh Mehta

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02-08-2024

(Relatively Weak)

Dodelson Modern Cosmology

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Harsh Mehta

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02-08-2024

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( Vikhlinin et al., 2006

arXiv:astro-ph/0507092 )

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( Bonafede et al., 2010 �arXiv:1009.1233 )

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How does the ALP background spectrum look like?

 

Harsh Mehta

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02-08-2024

 

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How is the ALP signal different from other signals?

Can be distinguished in pixel, spectral and spatial domain

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Harsh Mehta

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02-08-2024

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Cosmological

Harsh Mehta

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02-08-2024

(a) Variation with redshift

(b) Variation with Coupling constant

(b) Variation with Magnetic field steepening

(a) Variation with Electron density strength

Astrophysical

 

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Harsh Mehta

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02-08-2024

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Conclusion

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  • The ALP background signal will follow the distribution of galaxy clusters in the universe.

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  • The ALP power spectrum will differ from those of other signals.

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  • The ALP power spectrum dominates at low angular scales and increases with frequency.

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  • A Science case for CMB-S4

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Harsh Mehta

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02-08-2024

https://indico.cern.ch/

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Harsh Mehta

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02-08-2024

Thank you!!

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Email: hmehta.cosmo@gmail.com

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EXTRAS

Harsh Mehta

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02-08-2024

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Harsh Mehta

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02-08-2024

Mehta and Mukherjee, A Diffused Background from Axion-like Particles in the Microwave Sky, 2024

Mehta and Mukherjee, A power spectrum approach to the search for Axion-like Particles from resolved galaxy clusters using CMB as a backlight, 2024

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Cosmological Variations

Harsh Mehta

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02-08-2024

(a) Variation with redshift

(c) Variation with frequency

(b) Variation with Coupling constant

(b) Variation with Magnetic field steepening

(a) Variation with Electron density strength

(c) Variation with Cluster Mass

Astrophysical Variations

 

Fig.15

Fig.16

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SNR at different frequencies for various detectors

 

Harsh Mehta

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02-08-2024

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CMB photon-ALP resonant conversion

 

Harsh Mehta

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02-08-2024

Figure 3

(Equ.1)

(Equ.2)

(Equ.3)

(Equ.4)

(Equ.5)

Figure 4

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How will the ALP signal look like?

 

Harsh Mehta

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02-08-2024

Spectra of various signals

ALP Mass vs disk size

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Distribution of Halos in the Universe�

Harsh Mehta

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02-08-2024

z = 1.5

z = 0.5

z = 2.5

z = 3.5

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Summary statistics of the CMB: Power spectrum

 

Harsh Mehta

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02-08-2024