Orbits and Masses in the multiple system LHS 1070

We present a study of the orbits of the triple system LHS1070, with the aim to determine individual masses of its components. Sixteen new relative astrometric positions of the three components in the K band were obtained with NACO at the VLT, Omega CASS at the 3.5m telescope on Calar Alto, and other high-spatial-resolution instruments. We combine them with data from the literature and fit orbit models to the dataset. We derive an improved fit for the orbit of LHS1070B and C around each other, and an estimate for the orbit of B and C around A. The orbits are nearly coplanar, with a misalignment angle of less than 10{\deg}. The masses of the three components are M_A = 0.13 - 0.16 Msun, M_B = 0.077+/-0.005 Msun, and M_C = 0.071+/-0.004 Msun. Therefore, LHS1070C is certainly, and LHS1070B probably a brown dwarf. Comparison with theoretical isochrones shows that LHS1070A is either fainter or more massive than expected. One possible explanation would be that it is a binary. However, the close companion reported previously could not be confirmed.Comment: 9 pages, 8 figures, accepted by Astronomy and Astrophysic

STUDI PENGARUH PERUBAHAN PENGGUNAAN LAHAN UNTUK PREDIKSI PERUBAHAN SUHU LINGKUNGAN DENGAN MEMANFAATKAN SIG (Studi Kasus : Kota Malang, Jawa Timur)

Kota Malang merupakan kota pariwisata dan pusat kegiatan perindustrian menengah di Indonesia bagian timur yang mengalami perubahan dan perkembangan yang signifikan, hal ini mengakibatkan RTH (Ruang Terbuka Hijau) di kota ini makin berkurang seiring dengan perkembangannya. Penelitian ini dimaksud untuk mengetahui hubungan penggunaan lahan di Kota Malang dari tahun 2013 dan 2015. Berdasarkan data perubahan lahan tersebut, selanjutnya digunakan untuk menganalisis perubahan suhu lingkungan sehingga menghasilkan peta persebaran suhu di Kota Malang. Pengukuran suhu lingkungan ini dilakukan 3 kali sehari dalam jangka waktu 1 bulan, dengan waktu pengamatan yang sama di tahun 2013 dan 2015 untuk mendapatkan suhu rata-rata pagi, siang, sore dan harian. Pengukuran suhu dilakukan dengan menggunakan Thermometer Hygro Eiger serta lokasi sampel penggunaan lahan yang diambil koordinatnya menggunakan GPS Handheld. Selanjutnya, data pengamatan suhu dan data koordinat tersebut digunakan untuk analisis dengan peta penggunaan lahan di kota Malang untuk mengetahui perubahan suhu lingkungan antara tahun 2013 dan 2015. Hasil dari penelitian ini menunjukkan bahwa suhu rata-rata kota Malang mengalami kenaikan. Data tahun 2013 menunjukkan suhu rata-rata kota Malang sebesar 25,6°C - 26,8°C dan data tahun 2015 mengalami kenaikan yaitu 26,37°C - 28,56°C. Kecamatan yang memiliki suhu tertinggi adalah kecamatan Klojen sedangkan yang terendah adalah kecamatan Kedungkandang. Selain pengaruh penggunaan lahan, faktor seperti kepadatan dan aktivitas penduduk, kondisi lalu lintas dan kerapatan penutupan kanopi pohon menjadi pengaruh perubahan suhu di kota Malang. Kata Kunci : SIG, Suhu Lingkungan, Penggunaan Lahan, Kota Malan

Abelian Yang-Mills theory on Real tori and Theta divisors of Klein surfaces

The purpose of this paper is to compute determinant index bundles of certain families of Real Dirac type operators on Klein surfaces as elements in the corresponding Grothendieck group of Real line bundles in the sense of Atiyah. On a Klein surface these determinant index bundles have a natural holomorphic description as theta line bundles. In particular we compute the first Stiefel-Whitney classes of the corresponding fixed point bundles on the real part of the Picard torus. The computation of these classes is important, because they control to a large extent the orientability of certain moduli spaces in Real gauge theory and Real algebraic geometry.Comment: LaTeX, 44 pages, to appear in Comm. Math. Phy

CLAM, a continuous line alignment and monitoring method for RICH mirrors

A method is proposed for the angular alignment of RICH mirrors and for its monitoring, in particular for the COMPASS RICH-1 mirror system. Observing (by means of four cameras) apparent discontinuities in the images of continuous linear objects reflected by the mirrors surface, a relative misalignment of adjacent mirrors can be deduced and then corrected. The method can attain a sensitivity of at least 0.1 mrad, and can also be applied on-line to keep under control the stability of the mirrors during data taking

A 65 k.y. time series from sediment-hosted glasses reveals rapid transitions in ocean ridge magmas

Studies of ocean ridge magmatism have been hampered by the difficulty in constructing time-series data over more than a few thousand years. Sediment rapidly covers newly formed ocean crust, and older rocks, even when recovered from fault scarps, cannot be dated accurately. Ridge eruptions, however, disperse pyroclastic glass over distances as far as 5 km, and these glasses have been shown to persist for thousands of years in on-ridge sediment push cores. Here we present data on such glasses from a piston core that impacted basement in much older (600 ka) sediment. The age of deposition was determined using established stratigraphic methods to date the host sediment, yielding an average sample resolution of a few thousand years and a continuous 65 k.y. time series. The new time-series data show systematic temporal variations in magma compositions related to a change to the dynamics of crustal storage, which led to greater extents of pre-eruptive differentiation. Shortly thereafter was a small but discernable shift toward more enriched primary melt compositions. These events coincide with the onset of enhanced crustal production, previously identified using seismic data and interpreted to reflect the capture of a hotspot by the ridge. These results show the long-term preservation of pyroclastic glasses and suggest that the construction of high-resolution volcanic stratigraphy over a million years or more may be possible at ocean ridges, using multiple piston cores that impact basement. Sediment-hosted glasses have the potential to transform ocean ridges from the volcanic setting with the worst time-series data to that with the best

Correlation of the South Pole 94 data with 100microns and 408 MHz maps

We present a correlation between the ACME/SP94 CMB anisotropy data at 25 to 45 GHz with the IRAS/DIRBE data and the Haslam 408 MHz data. We find a marginal correlation between the dust and the Q-band CMB data but none between the CMB data and the Haslam map. While the amplitude of the correlation with the dust is larger than that expected from naive models of dust emission it does not dominate the sky emission.Comment: 6 pages, 4 figures. Accepted for publication in Astronomy and Astrophysic

Surgical Options for the Refractive Correction of Keratoconus: Myth or Reality

Keratoconus provides a decrease of quality of life to the patients who suffer from it. The treatment used as well as the method to correct the refractive error of these patients may influence on the impact of the disease on their quality of life. The purpose of this review is to describe the evidence about the conservative surgical treatment for keratoconus aiming to therapeutic and refractive effect. The visual rehabilitation for keratoconic corneas requires addressing three concerns: halting the ectatic process, improving corneal shape, and minimizing the residual refractive error. Cross-linking can halt the disease progression, intrastromal corneal ring segments can improve the corneal shape and hence the visual quality and reduce the refractive error, PRK can correct mild-moderate refractive error, and intraocular lenses can correct from low to high refractive error associated with keratoconus. Any of these surgical options can be performed alone or combined with the other techniques depending on what the case requires. Although it could be considered that the surgical option for the refracto-therapeutic treatment of the keratoconus is a reality, controlled, randomized studies with larger cohorts and longer follow-up periods are needed to determine which refractive procedure and/or sequence are most suitable for each case

Cloud-native databases : an application perspective

As cloud computing technologies evolve to better support hosted software applications, software development businesses are faced with a multitude of options to migrate to the cloud. A key concern is the management of data. Research on cloud-native applications has guided the construction of highly elastically scalable and resilient stateless applications, while there is no corresponding concept for cloud-native databases yet. In particular, it is not clear what the trade-offs between using self-managed database services as part of the application and provider-managed database services are. We contribute an overview about the available options, a testbed to compare the options in a systematic way, and an analysis of selected benchmark results produced during the cloud migration of a commercial document management application