Design And Testing Validation Of An Extendable Pressurized Tunnel For An Inflatable Lunar Habitat

In the design of the UND inflatable lunar habitat (ILH), the need for an extendable pressurized tunnel to link the habitat to a wheeled terrestrial vehicle (rover), and secure the connection between both elements is one of the critical problems to be solved in order to test the validity of the ILH concept. The design of an extendable pressurized tunnel is required in order to allow access to and from the rover without the use of pressure suits. It is expected than using an extendable tunnel will allow simple docking procedures. An experimental process is required to determine the best procedure to dock the pressurized rover with the habitat. This will be done by a number of tests to determine the docking position. Testing of the docking element, extension units, and docking position will be required. This will prove that this design of an extendable pressurized tunnel is a valid solution to the problem

Search for intermediate-mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo

International audienceIntermediate-mass black holes (IMBHs) span the approximate mass range 100−105 M⊙, between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∼150 M⊙ providing direct evidence of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200 M⊙ and effective aligned spin 0.8 at 0.056 Gpc−3 yr−1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc−3 yr−1.Key words: gravitational waves / stars: black holes / black hole physicsCorresponding author: W. Del Pozzo, e-mail: [email protected]† Deceased, August 2020