Dark Matter Distinguished by Skewed Microlensing in the “Dragon Arc”

Abstract Many microlensed stars discovered by JWST closely follow the winding critical curve of A370 along the “Dragon Arc” with m AB > 26.5, which we show comprises asymptotic giant branch stars microlensed by the observed level of diffuse cluster stars, corresponding to ≃1% of the dark matter density. Most events appear along the inner edge of the critical curve, following an asymmetric band of width ≃4.5 kpc that is skewed by −0.7 ± 0.2 kpc. This asymmetry, we argue, follows from the parity difference in caustic structure inherent to microlensing that extends to higher magnification in the negative parity regions. This parity difference predicts a modest net shift of −0.04 kpc to the inside of the cluster critical curve within a narrower band of ≃1.4 kpc than observed. Adding cold-dark-matter-like subhalos of 10 6−8 M ⊙ doubles the width, but detections are predicted to favor the outside of the critical curve, where the subhalos generate local Einstein rings, and subhalos inside the critical curve depress the magnification, reducing microlensing. Instead, the density perturbations of “wave dark matter” as a Bose–Einstein condensate ( ψ DM) can generate a wide band of corrugated critical curves with a large negative asymmetry. We find that a de Broglie wavelength of ≃10 pc reproduces the observed width of 4.5 kpc, with a negative skewness ≃−0.6 kpc, like the data, corresponding to a boson mass of ≃10 −22 eV, in agreement with dwarf galaxy dynamical estimates. Independently, we also find clear asymmetry in the Jupiter Arc, with 12 microlensed stars lying along the inside of the critical curve, like the Dragon Arc.

Authors

Institutions

Publication Details

Journal
The Astrophysical Journal Letters
Published
2024-12-23
DOI
https://doi.org/10.3847/2041-8213/ad9aa8
Citations
14
Primary Topic
Stellar, planetary, and galactic studies
Type
article
Field-Weighted Citation Impact
4.64

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Dark Matter Distinguished by Skewed Microlensing in the “Dragon Arc”

Jeremy Lim, Hayley Williams, Liliya L. R. Williams, Fengwu Sun et al.
14 citations
The Astrophysical Journal Letters
Stellar, planetary, and galactic studies
4.64
article

Dark Matter Distinguished by Skewed Microlensing in the “Dragon Arc”

Jeremy Lim, Hayley Williams, Liliya L. R. Williams, Fengwu Sun, Rogier A. Windhorst, Patrick L. Kelly, Tom Broadhurst, Sung Kei Li, Liang Dai, Katsuya T. Abe, Ashish Kumar Meena, Tao Liu, Yoshinobu Fudamoto, Jose M. Palencia, Masamune Oguri, Adi Zitrin, J. M. Diego, Alfred Amruth, Wenlei Chen, Paloma Morilla, Hiroki Kawai, George F. Smoot
article en
14 citations

Abstract

Abstract Many microlensed stars discovered by JWST closely follow the winding critical curve of A370 along the “Dragon Arc” with m AB > 26.5, which we show comprises asymptotic giant branch stars microlensed by the observed level of diffuse cluster stars, corresponding to ≃1% of the dark matter density. Most events appear along the inner edge of the critical curve, following an asymmetric band of width ≃4.5 kpc that is skewed by −0.7 ± 0.2 kpc. This asymmetry, we argue, follows from the parity difference in caustic structure inherent to microlensing that extends to higher magnification in the negative parity regions. This parity difference predicts a modest net shift of −0.04 kpc to the inside of the cluster critical curve within a narrower band of ≃1.4 kpc than observed. Adding cold-dark-matter-like subhalos of 10 6−8 M ⊙ doubles the width, but detections are predicted to favor the outside of the critical curve, where the subhalos generate local Einstein rings, and subhalos inside the critical curve depress the magnification, reducing microlensing. Instead, the density perturbations of “wave dark matter” as a Bose–Einstein condensate ( ψ DM) can generate a wide band of corrugated critical curves with a large negative asymmetry. We find that a de Broglie wavelength of ≃10 pc reproduces the observed width of 4.5 kpc, with a negative skewness ≃−0.6 kpc, like the data, corresponding to a boson mass of ≃10 −22 eV, in agreement with dwarf galaxy dynamical estimates. Independently, we also find clear asymmetry in the Jupiter Arc, with 12 microlensed stars lying along the inside of the critical curve, like the Dragon Arc.

The Astrophysical Journal LettersVol. 978(1)
Ikerbasque (ES), Oklahoma State University (US), Ben-Gurion University of the Negev (IL), Centre National de la Recherche Scientifique (FR), University of Minnesota (US), University of Arizona (US), Chiba University (JP), University of the Basque Country (ES), Hong Kong University of Science and Technology (HK), Université Paris Cité (FR), Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR), Laboratoire AstroParticule et Cosmologie (FR), Hong Kong Jockey Club (HK), Center for Astrophysics Harvard & Smithsonian (US), Institute for Advanced Study (DE), Instituto de Física de Cantabria (ES), Nano and Advanced Materials Institute (CN), Donostia International Physics Center (ES), Arizona State University (US), The University of Tokyo (JP), University of Hong Kong (HK), University of California, Berkeley (US)
National Science Foundation, National Aeronautics and Space Administration, Ministerio de Ciencia, Innovación y Universidades, United States-Israel Binational Science Foundation, Eusko Jaurlaritza, Euskal Herriko Unibertsitatea, Nuclear Safety and Security Commission, Goddard Space Flight Center, Japan Society for the Promotion of Science, Agencia Estatal de Investigación
Openalex Percentile: Top 5%
Stellar, planetary, and galactic studies
4.64
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.