We present the biggest up-to-date sample of edge-on galaxies with boxy/peanut-shaped (B/PS) bulges and X-structures. The sample was prepared using images from the Dark Energy Spectroscopic Instrument (DESI) Legacy catalogue and contains about 2000 galaxies. To find suitable candidates in catalogue, we made the assumption that the residues (original images minus model) of galaxies with B/PS bulges should exhibit a characteristic X-shape. Galaxies with such features were selected by eye and then used as input data for a neural network training, which was applied to a bigger sample of edge-on galaxies. Using the available data and the photometric models from the literature, we investigated the observational and statistical properties of the sample created. Comparing the B/D ratios for galaxies with and without B/PS bulges, we found that the B/D ratio for galaxies from our sample is statistically higher, with typical values in the range approximate to 0.2-0.5 depending on the decomposition procedure. We studied how the opening angles phi of the X-structure and the length of its rays are distributed in the formed sample and found them to be consistent with previous measurements and predictions from N-body models, e.g. phi greater than or similar to 25 degrees, but measured here for a much larger number of galaxies. We found a sharp increase in the B/PS bulge fraction for stellar masses log M-star greater than or similar to 10.4, but for edge-on galaxies, which complements the results of previous works. The sample can be used in future work to test various bar models and their relationship with B/PS bulges, as well as to study their stability and evolution.

Original languageEnglish
Pages (from-to)1371-1390
Number of pages20
JournalMonthly Notices of the Royal Astronomical Society
Volume512
Issue number1
DOIs
StatePublished - 22 Mar 2022

    Research areas

  • galaxies: bar, galaxies: bulges, galaxies: evolution, galaxies: fundamental parameters, galaxies: photometry, galaxies: structure, BOXY/PEANUT-SHAPED BULGES, BARRED GALAXIES, DATA RELEASE, SECULAR EVOLUTION, DISK GALAXIES, STELLAR BARS, BOXY BULGES, KINEMATICS, ROTATION, DECOMPOSITION

    Scopus subject areas

  • Physics and Astronomy(all)

ID: 93768298