Data on the multiplicity of F- and G-type dwarf stars within 67pc of the Sun are presented. This distance-limited sample based on the Hipparcos catalog contains 4847 primary stars (targets) with 0.5 90% complete. There are 2196 known stellar pairs, some of them belong to 361 hierarchical systems from triples to quintuples. Models of companion detection by radial velocity, astrometric acceleration, direct resolution, and common proper motion are developed. They serve to compute completeness for each target, using the information on its coverage collected here. About 80% of companions to the primary stars are detected, but the census of sub-systems in the secondary components is only about 30%. Masses of binary components are estimated from their absolute magnitudes or by other methods, the periods of wide pairs are evaluated from their projected separations. A third of binaries with periods shorter than ~100yr are spectroscopic and/or astrometric pairs with yet unknown periods and mass ratios. These data are used in the accompanying Paper II to derive unbiased statistics of hierarchical multiple systems.

From binaries to multiples I: Data on F and G dwarfs within 67 pc of the Sun

In order to determine an upper bound for the mass of the massive compact halo objets (MACHOs) we use the halo binaries contained in a recent catalog (Allen \& Monroy-Rodr\'{\i}guez 2013). To dynamically model their interactions with massive perturbers a Monte Carlo simulation is conducted, using an impulsive approximation method and assuming a galactic halo constituted by massive particles of a characteristic mass. The results of such simulations are compared with several subsamples of our improved catalog of candidate halo wide binaries. In accordance with Quinn et al. (2009) we also find our results to be very sensitive to the widest binaries. However, our larger sample, together with the fact that we can obtain galactic orbits for 150 of our systems, allows a more reliable estimate of the maximum MACHO mass than that obtained previously. If we employ the entire sample of 211 candidate halo stars we obtain an upper limit of $112 M_\sun$. However, using the 150 binaries in our catalog with computed galactic orbits we are able to refine our fitting criteria. Thus, for the 100 most halo-like binaries we obtain a maximum MACHO mass of $21-68 M_\sun$. Furthermore, we can estimate the dynamical effects of the galactic disk using binary samples that spend progressively shorter times within the disk. By extrapolating the limits obtained for our most reliable -albeit smallest- sample we find that as the time spent within the disk tends to zero the upper bound of the MACHO mass tends to less than $5 M_\sun$. The non-uniform density of the halo has also been taken into account, but the limit obtained, less than $5 M_\sun$, does not differ much from the previous one. Together with microlensing studies that provide lower limits on the MACHO mass, our results essentially exclude the existence of such objects in the galactic halo.

The end of the MACHO era- revisited: new limits on MACHO masses from halo wide binaries

A sample of 477 solar-type binaries within 67 pc with projected separations larger than 50 AU is studied by a new statistical method. Speed and direction of the relative motion are determined from the short observed arcs or known orbits, and their joint distribution is compared to the numerical simulations. By inverting the observed distribution with the help of simulations, we find that average eccentricity of wide binaries is 0.59±0.02 and the eccentricity distribution can be modelled as f(e) ¼ 1.2e + 0.4. However, wide binaries containing inner subsystems, i.e. triple or higher-order multiples, have significantly smaller eccentricities with the average e = 0.52 ± 0.05 and the peak at e » 0.5. We find that the catalog of visual orbits is strongly biased against large eccentricities. A marginal evidence of eccentricity increasing with separation (or period) is found for this sample. Comparison with spectroscopic binaries proves the reality of the controversial period-eccentricity relation. The average eccentricity does increase with binary period, being 0.39 for periods from 10 2 to 10 3 days and 0.59 for the binaries studied here (10 5 to 10 6 days).

Eccentricity distribution of wide binaries

Aims. We present new results from our ongoing multiplicity study of exoplanet host stars and present a list of 29 confirmed planet host multiple-star systems. Furthermore, we discuss the properties of these stellar systems and compare the properties of exoplanets detected in these systems with those of planets orbiting single stars. Methods. We used direct imaging to search for wide stellar and substellar companions of exoplanet host stars. With infrared and/or optical spectroscopy, we determined the spectral properties of the newly-found co-moving companions. Results. We obtained infrared H -a ndK-band spectra of the co-moving companion GJ 3021 B. The infrared spectra and the apparent H-band photometry of the companion is consistent with an M3–M5 dwarf at the distance of the exoplanet host star. HD 40979 AB is a wide planet host stellar system, with a separation of ∼ 6400 AU. The companion to the exoplanet host star turned out to be a close stellar pair with a projected separation of ∼130 AU, hence, this system is a new member of those rare planet host triple-star systems of which only three other systems are presently known. HD 27442 AB is a wide binary system listed in the Washington Double Star Catalogue, whose common proper motion was recently confirmed. This system is composed of the subgiant HD 27442 A hosting the exoplanet, and its faint companion HD 27442 B. The visible and infrared J-, H-, and KS-band photometry of HD 27442 B at the distance of the primary star shows that the companion is probably a white dwarf. Our multi-epochs SofI imaging observations confirm this result and even refine the suggested physical characteristics of HD 27442 B. This companion should be a relatively young, hot white dwarf with an effective temperature of ∼14 400 K, and cooling age of ∼220 Myr. Finally, we could unambiguously confirm the white dwarf nature of HD 27442 B with follow-up optical and infrared spectroscopy. The spectra of the companion show Hydrogen absorption features of the Balmer, Paschen, and Bracket series. With its subgiant primary and the white-dwarf companion, the HD 27442 AB system is the most evolved planet host stellar system known today. The mass-period and eccentricity-period correlation of planets around single stars and those residing in multiple-star systems seem different for the short-period planets. The distribution functions of planet orbital elements (P, e) are identical, while the mass-distribution (m sin(i)) exhibits one difference. While both planet populations exhibit a peak in their mass-distribution at about 1 MJup, the frequency of more massive planets continually decreases in single-star systems, whereas the mass-distribution of planets residing in multiple-star systems exhibits a further peak at about 4 MJup. This indicates that the mass-distributions of the two planet populations might differ in the intermediate mass-range between 2 and 6 MJup.

/pdf/the-multiplicity-of-exoplanet-host-stars-spectroscopic-38cynhf6ty.pdf

The multiplicity of exoplanet host stars - Spectroscopic confirmation of the companions GJ 3021 B and HD 27442 B, one new planet host triple-star system, and global statistics

We conducted a survey of nearby binary systems composed of main sequence stars of spectral types F and G in order to improve our understanding of the hierarchical nature of multiple star systems. Using Robo-AO, the first robotic adaptive optics instrument, we collected high angular resolution images with deep and well-defined detection limits in the SDSS $i'$ band. A total of 695 components belonging to 595 systems were observed. We prioritized observations of faint secondary components with separations over $10''$ to quantify the still poorly constrained frequency of their sub-systems. Of the 214 secondaries observed, 39 contain such subsystems; 19 of those were discovered with Robo-AO. The selection-corrected frequency of secondary sub-systems with periods from $10^{3.5}$ to $10^5$ days is 0.12$\pm$0.03, the same as the frequency of such companions to the primary. Half of the secondary pairs belong to quadruple systems where the primary is also a close pair, showing that the presence of sub-systems in both components of the outer binary is correlated. The relatively large abundance of 2+2 quadruple systems is a new finding, and will require more exploration of the formation mechanism of multiple star systems. We also targeted close binaries with periods less than 100~yr, searching for their distant tertiary components, and discovered 17 certain and 2 potential new triples. In a sub-sample of 241 close binaries, 71 have additional outer companions. The overall frequency of tertiary components is not enhanced, compared to all (non-binary) targets, but in the range of outer periods from $10^6$ to $10^{7.5}$ days (separations on the order of 500~AU), the frequency of tertiary components is 0.16$\pm$0.03, exceeding by almost a factor of two the frequency of similar systems among all targets (0.09).

/pdf/a-survey-of-the-high-order-multiplicity-of-nearby-solar-type-nf7v0gp9uj.pdf

A survey of the high order multiplicity of nearby solar-type binary stars with Robo-AO

We observed nine binary stars with ephemerides on the Sixth Catalog of Orbits of Visual Binary Stars with the objective of corroborating the predictions on the Catalog. Our results show agreement with the predictions of separation (ρ), but found a slight difference with the predictions of position angle (Θ). Recent measurements reported in the Washington Double Star Catalog tend to agree with our observations. Vol. 2 No. 4 Fall 2006 Page 139 Journal of Double Star Observations A Report on the Observation of Selected Binary Stars with Ephemerides. . . ease. To check the results from the aforementioned method the students use the Software AIP for Windows7, which has a routine for the calculation of position angle and separation. Results Our results are summarized in the tables below. The first 3 columns of the tables show recent measurements of separation (ρ) and position angle (Θ) in the WDS. The second set of 3 columns show predictions from the Sixth Catalog of Orbits. The last four columns show our measurements. N, the number of observations, is one in all cases We have been measuring Sigma Corona Borealis often as part of our routine observations of binary stars at the N.U.R.O. telescope but all other binaries in the table constitute first time observing for us. We have chosen to measure these pairs even though they have lots of reported measurements, because we believe there is a lot of scientific merit in making sure the “model” works properly by observing and comparing the results plus the added bonus that you are also checking if your measurements yield reasonable results. The values in Table I seem to indicate that our ρ values are in close agreement with other observations and also in close agreement with the ephemerides, except for STF 2486 AB where we get a spurious result. However, the results for position angle Θ differ from the prediction although, in general, tend to fall closer to the other reported values in the WDS. We have used the Data Request form of the WDS8 to gather information of some of the stars we observed and would like to recommend this efficient service from the WDS. The information obtained is priceless and gives the reader a clear notion of the binary system one is studying. (Continued on page 141) Recent measurements from WDS Sixth Catalog Ephemerides UPR at Humacao Measusrements year ρ arcsc Θ degree year ρ arcsc Θ degrees year ρ arcsc Θ degrees N

A Report on the Observation of Selected Binary Stars with Ephemerides in the Sixth Catalog of Orbits of Visual Binary Stars

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Morgan Spangle

Author Tools

Chat about Author

Papers

A Report on the Observation of Selected Binary Stars with Ephemerides in the Sixth Catalog of Orbits of Visual Binary Stars