Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33
Classical Cepheids can be used as age indicators due to well-established period–age and period–age–color relations. G. De Somma et al. refined these relations by including a metallicity term and different mass–luminosity assumptions. In this study, we apply the period–age–metallicity relation for th...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/adcf92 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849313779136856064 |
|---|---|
| author | Giulia De Somma Marcella Marconi Vincenzo Ripepi Santi Cassisi Roberto Molinaro Ilaria Musella Teresa Sicignano Erasmo Trentin |
| author_facet | Giulia De Somma Marcella Marconi Vincenzo Ripepi Santi Cassisi Roberto Molinaro Ilaria Musella Teresa Sicignano Erasmo Trentin |
| author_sort | Giulia De Somma |
| collection | DOAJ |
| description | Classical Cepheids can be used as age indicators due to well-established period–age and period–age–color relations. G. De Somma et al. refined these relations by including a metallicity term and different mass–luminosity assumptions. In this study, we apply the period–age–metallicity relation for the first time to samples of classical Cepheids in M31 and M33. For both galaxies, we consider Cepheid coordinates and spatial distributions, along with the metallicity gradient by D. Zaritsky et al. and L. Magrini et al. to provide a metallicity estimate for each pulsator. Therefore, by applying the period–age–metallicity relation, we derive the individual ages of each Cepheid. By combining the individual ages and spatial distributions of classical Cepheids in M31 and M33, we built detailed age maps for both galaxies. Our analysis confirms a radial age gradient, with younger Cepheids preferentially found toward the galactic center. In M31, we confirm an outer ring at ∼11 kpc, consistent with previous studies, and identify for the first time an inner ring at ∼7 kpc, possibly associated with star formation episodes. Comparing age gradients at different angles, we find a consistent general trend of ages increasing monotonically with radius. At the same time, we observe smaller-scale differences, particularly in the 90°–180° quadrant, suggesting asymmetric star formation and possible dynamical influences. In contrast, M33 displays a steeper global age gradient, indicating a higher concentration of young stars toward its center. This study highlights the utility of Cepheids as stellar population tracers, providing insights into the star formation and dynamical evolution of spiral galaxies. Future works will extend this methodology to additional galaxies. |
| format | Article |
| id | doaj-art-fd7f3992e760418581a201bdec7d97a8 |
| institution | Kabale University |
| issn | 2041-8205 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj-art-fd7f3992e760418581a201bdec7d97a82025-08-20T03:52:39ZengIOP PublishingThe Astrophysical Journal Letters2041-82052025-01-019842L6010.3847/2041-8213/adcf92Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33Giulia De Somma0https://orcid.org/0000-0002-5819-3461Marcella Marconi1https://orcid.org/0000-0002-1330-2927Vincenzo Ripepi2https://orcid.org/0000-0003-1801-426XSanti Cassisi3https://orcid.org/0000-0001-5870-3735Roberto Molinaro4https://orcid.org/0000-0003-3055-6002Ilaria Musella5https://orcid.org/0000-0001-5909-6615Teresa Sicignano6https://orcid.org/0009-0004-7523-0799Erasmo Trentin7https://orcid.org/0000-0002-3899-566XINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.it; INAF-Osservatorio Astronomico d’Abruzzo , Via Maggini sn, 64100 Teramo, Italy; Istituto Nazionale di Fisica Nucleare (INFN)—Sez. di Napoli, Compl. Univ. di Monte S. Angelo , Edificio G, Via Cinthia, I-80126, Napoli, ItalyINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.itINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.itINAF-Osservatorio Astronomico d’Abruzzo , Via Maggini sn, 64100 Teramo, Italy; Istituto Nazionale di Fisica Nucleare (INFN)—Sezione di Pisa, Universitá di Pisa , Largo Pontecorvo 3, 56127 Pisa, ItalyINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.itINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.itINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.it; Istituto Nazionale di Fisica Nucleare (INFN)—Sez. di Napoli, Compl. Univ. di Monte S. Angelo , Edificio G, Via Cinthia, I-80126, Napoli, Italy; European Southern Observatory , Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany; Scuola Superiore Meridionale , Largo S. Marcellino 10, 80138 Napoli, ItalyINAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16, 80131 Napoli, Italy ; giulia.desomma@inaf.itClassical Cepheids can be used as age indicators due to well-established period–age and period–age–color relations. G. De Somma et al. refined these relations by including a metallicity term and different mass–luminosity assumptions. In this study, we apply the period–age–metallicity relation for the first time to samples of classical Cepheids in M31 and M33. For both galaxies, we consider Cepheid coordinates and spatial distributions, along with the metallicity gradient by D. Zaritsky et al. and L. Magrini et al. to provide a metallicity estimate for each pulsator. Therefore, by applying the period–age–metallicity relation, we derive the individual ages of each Cepheid. By combining the individual ages and spatial distributions of classical Cepheids in M31 and M33, we built detailed age maps for both galaxies. Our analysis confirms a radial age gradient, with younger Cepheids preferentially found toward the galactic center. In M31, we confirm an outer ring at ∼11 kpc, consistent with previous studies, and identify for the first time an inner ring at ∼7 kpc, possibly associated with star formation episodes. Comparing age gradients at different angles, we find a consistent general trend of ages increasing monotonically with radius. At the same time, we observe smaller-scale differences, particularly in the 90°–180° quadrant, suggesting asymmetric star formation and possible dynamical influences. In contrast, M33 displays a steeper global age gradient, indicating a higher concentration of young stars toward its center. This study highlights the utility of Cepheids as stellar population tracers, providing insights into the star formation and dynamical evolution of spiral galaxies. Future works will extend this methodology to additional galaxies.https://doi.org/10.3847/2041-8213/adcf92Cepheid variable starsSpiral galaxiesAndromeda GalaxyTriangulum GalaxyStellar evolutionStellar pulsations |
| spellingShingle | Giulia De Somma Marcella Marconi Vincenzo Ripepi Santi Cassisi Roberto Molinaro Ilaria Musella Teresa Sicignano Erasmo Trentin Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 The Astrophysical Journal Letters Cepheid variable stars Spiral galaxies Andromeda Galaxy Triangulum Galaxy Stellar evolution Stellar pulsations |
| title | Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 |
| title_full | Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 |
| title_fullStr | Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 |
| title_full_unstemmed | Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 |
| title_short | Spatial Age Distribution of Classical Cepheids in Spiral Galaxies: The Cases of M31 and M33 |
| title_sort | spatial age distribution of classical cepheids in spiral galaxies the cases of m31 and m33 |
| topic | Cepheid variable stars Spiral galaxies Andromeda Galaxy Triangulum Galaxy Stellar evolution Stellar pulsations |
| url | https://doi.org/10.3847/2041-8213/adcf92 |
| work_keys_str_mv | AT giuliadesomma spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT marcellamarconi spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT vincenzoripepi spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT santicassisi spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT robertomolinaro spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT ilariamusella spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT teresasicignano spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 AT erasmotrentin spatialagedistributionofclassicalcepheidsinspiralgalaxiesthecasesofm31andm33 |