The Inner and Outer Shock Layers of Bow Shocks in Cataclysmic Variables

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ilkiewicz, Krystian, Knigge, Christian, Scaringi, Simone, Segura, Noel Castro, del Palacio, Santiago, Veresvarska, Martina
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908881806950400
author Ilkiewicz, Krystian
Knigge, Christian
Scaringi, Simone
Segura, Noel Castro
del Palacio, Santiago
Veresvarska, Martina
author_facet Ilkiewicz, Krystian
Knigge, Christian
Scaringi, Simone
Segura, Noel Castro
del Palacio, Santiago
Veresvarska, Martina
contents Bow shocks around cataclysmic variables (CVs) have traditionally been identified with a single bright optical arc. This feature has been interpreted as the bow shock formed by the interaction between a sustained outflow and the interstellar medium (ISM). We show that this interpretation is incomplete. Generic wind-ISM interaction theory predicts a two-shock configuration consisting of an inner terminal wind (reverse) shock and an outer forward shock, separated by a hot, low-density shocked wind cavity. Using archival ultraviolet, optical, and infrared imaging of the nova-like systems BZ Cam and V341 Ara, and the polar 1RXS J052832.5+283824, we find that the nebulae around all three systems exhibit this layered structure. In each case, the previously identified bow shock bright in Halpha and [OIII] corresponds to a compact inner arc, while additional emission components reveal a more extended morphology. Specifically, each system shows an outer arc detected in mid-infrared images, and the region between the optical and infrared arcs is filled with faint Halpha emission and, where available, far ultraviolet emission. We identify this infrared arc, reported here for the first time in these systems, as the sweep-up boundary of the forward shock, while the bright inner optical arc corresponds to the terminal wind shock rather than the forward shock as previously assumed. These results reveal that the true extent and layered structure of bow shocks around CVs only become apparent when observations extend beyond the optical band.
format Preprint
id arxiv_https___arxiv_org_abs_2603_11742
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The Inner and Outer Shock Layers of Bow Shocks in Cataclysmic Variables
Ilkiewicz, Krystian
Knigge, Christian
Scaringi, Simone
Segura, Noel Castro
del Palacio, Santiago
Veresvarska, Martina
Solar and Stellar Astrophysics
Astrophysics of Galaxies
Bow shocks around cataclysmic variables (CVs) have traditionally been identified with a single bright optical arc. This feature has been interpreted as the bow shock formed by the interaction between a sustained outflow and the interstellar medium (ISM). We show that this interpretation is incomplete. Generic wind-ISM interaction theory predicts a two-shock configuration consisting of an inner terminal wind (reverse) shock and an outer forward shock, separated by a hot, low-density shocked wind cavity. Using archival ultraviolet, optical, and infrared imaging of the nova-like systems BZ Cam and V341 Ara, and the polar 1RXS J052832.5+283824, we find that the nebulae around all three systems exhibit this layered structure. In each case, the previously identified bow shock bright in Halpha and [OIII] corresponds to a compact inner arc, while additional emission components reveal a more extended morphology. Specifically, each system shows an outer arc detected in mid-infrared images, and the region between the optical and infrared arcs is filled with faint Halpha emission and, where available, far ultraviolet emission. We identify this infrared arc, reported here for the first time in these systems, as the sweep-up boundary of the forward shock, while the bright inner optical arc corresponds to the terminal wind shock rather than the forward shock as previously assumed. These results reveal that the true extent and layered structure of bow shocks around CVs only become apparent when observations extend beyond the optical band.
title The Inner and Outer Shock Layers of Bow Shocks in Cataclysmic Variables
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2603.11742