{"title":"Head-on collisions of fuzzy/cold dark matter subhalos","authors":"Hyeonmo Koo","doi":"10.1007/s40042-025-01420-8","DOIUrl":null,"url":null,"abstract":"<div><p>We perform head-on collision simulations of compact dark matter subhalos using distinct numerical methods for fuzzy dark matter (FDM) and cold dark matter (CDM) models. For FDM, we solve the Schrödinger–Poisson equations with a pseudo-spectral solver, while for CDM, we utilize a smoothed particle hydrodynamics <i>N</i>-body code. Our results show that velocity decrease of subhalos is significantly greater in FDM model than in CDM, particularly at lower initial velocities, attributed to gravitational cooling—a unique mechanism of stabilizing in FDM with dissipating kinetic energy. This stark contrast in energy dissipation between two DM models suggests that FDM may offer valuable insights into understanding the dynamic behaviors of DM during galaxy cluster collisions, such as those observed in the Bullet cluster and Abell 520. These findings strongly suggest that FDM is not only capable of explaining these complex astrophysical phenomena but also serves as a compelling alternative to the traditional CDM model, offering resolutions to longstanding discrepancies in DM behavior.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"87 4","pages":"430 - 440"},"PeriodicalIF":0.9000,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Korean Physical Society","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1007/s40042-025-01420-8","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
We perform head-on collision simulations of compact dark matter subhalos using distinct numerical methods for fuzzy dark matter (FDM) and cold dark matter (CDM) models. For FDM, we solve the Schrödinger–Poisson equations with a pseudo-spectral solver, while for CDM, we utilize a smoothed particle hydrodynamics N-body code. Our results show that velocity decrease of subhalos is significantly greater in FDM model than in CDM, particularly at lower initial velocities, attributed to gravitational cooling—a unique mechanism of stabilizing in FDM with dissipating kinetic energy. This stark contrast in energy dissipation between two DM models suggests that FDM may offer valuable insights into understanding the dynamic behaviors of DM during galaxy cluster collisions, such as those observed in the Bullet cluster and Abell 520. These findings strongly suggest that FDM is not only capable of explaining these complex astrophysical phenomena but also serves as a compelling alternative to the traditional CDM model, offering resolutions to longstanding discrepancies in DM behavior.
期刊介绍:
The Journal of the Korean Physical Society (JKPS) covers all fields of physics spanning from statistical physics and condensed matter physics to particle physics. The manuscript to be published in JKPS is required to hold the originality, significance, and recent completeness. The journal is composed of Full paper, Letters, and Brief sections. In addition, featured articles with outstanding results are selected by the Editorial board and introduced in the online version. For emphasis on aspect of international journal, several world-distinguished researchers join the Editorial board. High quality of papers may be express-published when it is recommended or requested.