Galactic bulge population II Cepheids in the VVV survey: period-luminosity relations and a distance to the Galactic centre

Bhardwaj, Anupam; Rejkuba, M.; Minniti, D.; Surot, F.; Valenti, E.; Zoccali, M.; Gonzalez, O. A.; Romaniello, M.; Singh, Harinder P.

doi:10.1051/0004-6361/201730841

Cited by 42 publications

(44 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…13 shows the histogram of distances to individual Miras towards the Galactic Center. Our distance estimates using mean-light are similar to that of Matsunaga et al (2009) and the peak of the distribution is consistent with the ∼ 0.3% geometric distance (∼ 8.18 kpc) to the Galactic center (Gravity Collaboration et al 2019), and with measurements based on RR Lyrae and Type II Cepheids (Dékány et al 2013;Bhardwaj et al 2017). However, the peak of the distribution using max-light PLRs shows an offset towards larger distances but is consistent within the uncertainties.…”

Section: Distance Between the Magellanic Cloudssupporting

confidence: 90%

Multiwavelength Period–Luminosity and Period–Luminosity–Color Relations at Maximum Light for Mira Variables in the Magellanic Clouds

Bhardwaj

Rejkuba

et al. 2019

ApJ

View full text Add to dashboard Cite

We present Period-Luminosity and Period-Luminosity-Color relations at maximum-light for Mira variables in the Magellanic Clouds using time-series data from the Optical Gravitational Lensing Experiment (OGLE-III) and Gaia data release 2. The maximum-light relations exhibit a scatter typically up to ∼ 30% smaller than their mean-light counterparts. The apparent magnitudes of Oxygen-rich Miras at maximum-light display significantly smaller cycle-to-cycle variations than at minimum-light. High-precision photometric data for Kepler Mira candidates also exhibit stable magnitude variations at the brightest epochs while their multi-epoch spectra display strong Balmer emission lines and weak molecular absorption at maximum-light. The stability of maximum-light magnitudes for Miras possibly occurs due to the decrease in the sensitivity to molecular bands at their warmest phase. At near-infrared wavelengths, the Period-Luminosity relations of Miras display similar dispersion at mean and maximum-light with limited time-series data in the Magellanic Clouds. A kink in the Oxygen-rich Mira Period-Luminosity relations is found at 300 days in the V I-bands which shifts to longer-periods (∼ 350 days) at near-infrared wavelengths. Oxygen-rich Mira Period-Luminosity relations at maximum-light provide a relative distance modulus, ∆µ = 0.48 ± 0.08 mag, between the Magellanic Clouds with a smaller statistical uncertainty than the mean-light relations. The maximum-light properties of Miras can be very useful for stellar atmosphere modeling and distance scale studies provided their stability and the universality can be established in other stellar environments in the era of extremely large telescopes.

show abstract

Section: Distance Between the Magellanic Cloudssupporting

confidence: 90%

Multiwavelength Period–Luminosity and Period–Luminosity–Color Relations at Maximum Light for Mira Variables in the Magellanic Clouds

Bhardwaj

Rejkuba

et al. 2019

ApJ

View full text Add to dashboard Cite

show abstract

“…Despite being much less numerous than RRLs (the Galactic Bulge hosts almost 70,000 RRLs but only around 1,000 T2Cs Soszyński et al 2014Soszyński et al , 2017Soszyński et al , 2019, T2Cs are from one to five mag brighter. This means that their detection in high extinction environments (e.g., the Galactic Bulge, Bhardwaj et al 2017b;Braga et al 2018aBraga et al , 2019 is easier, but also that they can be identified and characterized in external galaxies. Indeed, T2Cs have been found near M31 (Kodric et al 2018) in M101 and M106 (Stetson et al 1998;Macri et al 2006;Majaess et al 2009), and Article number, page 1 of 15 arXiv:2010.06368v1 [astro-ph.SR] 13 Oct 2020 A&A proofs: manuscript no.…”

Section: Introductionmentioning

confidence: 99%

Separation between RR Lyrae and type II Cepheids and their importance for a distance determination: the case of omega Cen

Braga

Bono

Fiorentino

et al. 2020

A&A

View full text Add to dashboard Cite

The separation between RR Lyrae (RRLs) and type II Cepheid (T2Cs) variables based on their period is debated. Both types of variable stars are distance indicators, and we aim to promote the use of T2Cs as distance indicators in synergy with RRLs. We adopted new and existing optical and near-infrared (NIR) photometry of ω Cen to investigate several diagnostics (color-magnitude diagram, Bailey diagram, Fourier decomposition of the light curve, and amplitude ratios) for their empirical separation. We found that the classical period threshold at one day is not universal and does not dictate the evolutionary stage: V92 has a period of 1.3 days but is likely to be still in its core helium-burning phase, which is typical of RRLs. We also derived NIR period-luminosity relations and found a distance modulus of 13.65 ± 0.07 (err.) ± 0.01 (σ) mag, in agreement with the recent literature. We also found that RRLs and T2Cs obey the same period-luminosity relations in the NIR. This equivalence provides the opportunity of adopting RRLs+T2Cs as an alternative to classical Cepheids to calibrate the extragalactic distance scale.

show abstract

“…There are other environments with T2C stars including the Large Magellanic Cloud (Soszyński et al 2008 the Small Magellanic Cloud (Soszyński et al 2010), the Fornax system (Bersier & Wood 2002), and the Galactic Bulge (Bhardwaj et al 2017), but none of them have been investigated for their metallicity.…”

Section: Kinematics Of T2c In Globular Clustersmentioning

confidence: 99%

Kinematics of Type II Cepheids of the Galactic Halo

Wallerstein

Farrell

2018

View full text Add to dashboard Cite

In a step toward understanding the origin of the Galactic Halo, we have reexamined Type II Cepheids (T2C) in the field with new input from the second data release (DR2) of Gaia. For 45 T2C with periods from 1 to 20 days, parallaxes, proper motions, and [Fe/H] values are available for 25 stars. Only 5 show [Fe/H] < -1.5, while the remaining stars show thick disk kinematics and [Fe/H] > -0.90. We have compared the T2C stars of the field with their cousins in the globular clusters of the Halo and found that the globular clusters with T2C stars show metallicities and kinematics of a pure Halo population. The globulars may have formed during the overall collapse of the Galaxy while the individual thick disk T2C stars may have been captured from small systems that self-enriched prior to capture. The relationship of these two populations to the micro-galaxies currently recognized as surrounding the Galaxy is unclear.

show abstract

Galactic bulge population II Cepheids in the VVV survey: period-luminosity relations and a distance to the Galactic centre

Cited by 42 publications

References 70 publications

Multiwavelength Period–Luminosity and Period–Luminosity–Color Relations at Maximum Light for Mira Variables in the Magellanic Clouds

Multiwavelength Period–Luminosity and Period–Luminosity–Color Relations at Maximum Light for Mira Variables in the Magellanic Clouds

Separation between RR Lyrae and type II Cepheids and their importance for a distance determination: the case of omega Cen

Kinematics of Type II Cepheids of the Galactic Halo

Contact Info

Product

Resources

About