We present relation of the mean I-band brightness of red clump stars on metallicity. Red clump stars were proposed to be a very attractive standard candle for distance determination. The calibration is based on 284 nearby red giant stars whose high-quality spectra made it possible to determine accurate individual metal abundances. High-quality parallaxes (sigmapi&solm0;pi<10%) and photometry of these very bright stars come from Hipparcos measurements. Metallicity of the sample covers a large range: -0.6 dex<&sqbl0;Fe&solm0;H&sqbr0;<+0.2 dex. We find a weak dependence of the mean I-band brightness on metallicity ( approximately 0.13 mag dex-1). What is more important, the range of metallicity of the Hipparcos sample partially overlaps with metallicity of field giants in the LMC, thus making it possible to determine the distance to the LMC by almost direct comparison of brightness of the local Hipparcos red clump giants with that of LMC stars. Photometry of field red clump giants in nine low-extinction fields of the LMC halo collected during the OGLE II microlensing survey compared with the Hipparcos red clump stars data yields the distance modulus to the LMC: &parl0;m-M&parr0;LMC=18.24+/-0.08 mag.

Download full-text PDF

Source
http://dx.doi.org/10.1086/312513DOI Listing

Publication Analysis

Top Keywords

red clump
12
clump stars
12
optical gravitational
4
gravitational lensing
4
lensing experiment
4
red
4
experiment red
4
stars
4
stars distance
4
distance indicator
4

Similar Publications

Lymphovascular Tumoral Emboli in Inflammatory Breast Cancer Result from Haptotaxis-Mediated Encircling Lymphangiogenesis.

Lymphatics

December 2024

Department of Pathology, Anatomy and Cell Biology and the Clinical and Translational Research Center of Excellence, Meharry Medical College, 1005 Dr. D.B. Todd Jr. Boulevard, Nashville, TN 37208, USA.

Inflammatory breast cancer (IBC) is characterized by numerous tumor emboli within lymphatics. In a recent study, we observed tumor embolic budding both in vitro and in vivo within lymphovascular spaces and proposed this to account for the plethora of tumor emboli seen in IBC. These observations did not address, however, how lymphovascular invasion is initiated or the mechanisms involved.

View Article and Find Full Text PDF
Article Synopsis
  • Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia where hemolysis occurs due to the activation of the classical complement pathway, with unclear incidence in pregnant women.
  • A case study of a 37-year-old woman undergoing a repeat Cesarean section revealed her anemia (hemoglobin 7.9 g/dL) was linked to CAD and required 20 blood transfusions throughout her pregnancy.
  • The management included preventing hypothermia to reduce hemolysis, utilizing spinal anesthesia and bilateral TAP blocks for effective pain control during the surgery.
View Article and Find Full Text PDF

The effects of chlorpyrifos, a frequently detected organophosphate in aquatic ecosystems, on biochemical (protein and glycogen) contents and oxidative enzyme activities (catalase and lipid peroxidation) in liver, muscle and gill tissues of three freshwater fish Trichogaster fasciata, Mystus vittatus and Heteropneustes fossilis were evaluated after 21-day exposure to 1 and 10% of 96 h LC of this pesticide, which were 1.63 and 16.3 µg L; 5.

View Article and Find Full Text PDF

Background/objectives: The high consumption of purine-rich meat is associated with hyperuricemia. However, there is limited evidence linking the consumption of red and processed meat to the genetic risk of hyperuricemia. We investigated the relationship between various combinations of red and processed meat consumption and the polygenic risk scores (PRSs) and the incidence of hyperuricemia in middle-aged Koreans.

View Article and Find Full Text PDF

Validation of the Sysmex XN-V hematology analyzer for feline specimens.

Vet Clin Pathol

September 2024

Département des Sciences Cliniques des Animaux de Compagnie et de Sport, Université de Toulouse, ENVT, Toulouse, France.

Background: The Sysmex XN-V is derived from the new Sysmex XN series of human hematology analyzers. The main changes from the previously validated XT-2000iV analyzer include an optic-fluorescent analysis for platelets and a nucleated red blood cell (NRBC) count.

Objective: We aimed to validate the Sysmex XN-V for feline blood following the American College for Veterinary Clinical Pathology and International Council for Standardization in Hematology recommendations.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!