Microlensing at cosmological distances: Event rate predictions in the Warhol arc of MACS 0416

Highly magnified stars (μ>100) are now routinely identified as transient events at cosmological distances thanks to microlensing by intra-cluster stars near the critical curves of galaxy clusters. Using the James Webb Space Telescope (JWST) in combination with the Hubble Space Telescope, we outli...

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Detalles Bibliográficos
Autores: Palencia, Jose María, Diego, José María, Dai, Liang, Pascale, Massimo, Windhorst, Rogier A., Koekemoer, Anton M., Li, Sung Kei, Kavanagh, Bradley J., Sun, Fengwu, Alfred, Amruth, Meena, Ashish Kumar, Broadhurst, Tom, Kelly, Patrick L., Perera, Derek, Williams, Hayley, Zitrin, Adi
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/398742
Acceso en línea:http://hdl.handle.net/10261/398742
Access Level:acceso abierto
Palabra clave:Gravitational lensing: strong
Gravitational lensing: micro
Methods: observational
Stars: abundances
Stars: AGB and post-AGB
Galaxies: high-redshift
Descripción
Sumario:Highly magnified stars (μ>100) are now routinely identified as transient events at cosmological distances thanks to microlensing by intra-cluster stars near the critical curves of galaxy clusters. Using the James Webb Space Telescope (JWST) in combination with the Hubble Space Telescope, we outline here an analytical framework that is applied to the Warhol arc (at z = 0.94) in the MACS 0416 galaxy cluster (at z = 0.396), where over a dozen microlensed stars have been detected to date. This method is general and can be applied to other lensed arcs. Within this lensed galaxy, we fit the spatially resolved spectral energy distribution spanned by eight JWST-NIRCam filters combined with three ACS filters, for accurate lensed star predictions in 2D. With this tool we can generate 2D maps of microlensed stars for well-resolved arcs in general, incorporating wavelength dependence and limiting apparent magnitude. These maps can be directly compared with planned cadenced campaigns from JWST and Hubble, offering a means to constrain the initial mass function and the level of dark matter substructure.