Month: September 2022

METHOD. “Using these ingredients, together with the current generation of stellar evolution codes, we can provide a grounded estimate of the global distribution of black holes as a function of black hole mass and galaxy stellar mass. With this as a starting point, we are able to quantify the astrophysical parameters needed to produce the observed BBH merger signals observed.” (BBH = binary black hole). https://lnkd.in/d8Jh7TB View in LinkedIn

NOMENCLATURE. “In astronomy, metallicity is the abundance of elements present in an object that are heavier than hydrogen and helium. Most of the normal physical matter in the Universe is either hydrogen or helium, and astronomers use the word "metals" as a convenient short term for "all elements except hydrogen and helium". (ie: a measure of nucleosynthesis in stars). https://lnkd.in/d8DupZu View in LinkedIn

METALLICITIES. “Important to all of these investigations is the realization that massive black hole formation is suppressed in stellar populations with higher metallicites.” https://lnkd.in/d8Jh7TB View in LinkedIn

BLACK HOLE MASS. “For example, according to the calculations of Spera et al, a star of mass ≃90M⊙ will be required to produce a remnant of mass mbh = 30 M⊙ if its metallicity is Z/Z⊙ = −0.5. A more metal poor star (−1.5) will need to be only ≃33M⊙ to produce a 30 M⊙ BBH remnant.” (BBH = binary black hole; M⊙ = unit of stellar mass in suns). https://lnkd.in/d8Jh7TB View in LinkedIn

NUCLEOSYNTHESIS. “We see that for high metallicities (Z ≳ −1.5), a very large stellar progenitor (≳90M⊙) will be required to produce the massive black holes of the type that have been observed in mergers by LIGO. Lower metallicity populations require less extreme progenitors.” (LIGO = an observatory; M⊙ = unit of stellar mass in suns). https://lnkd.in/d8Jh7TB View in LinkedIn

PREVALENT BLACK HOLES. “Fig. 3 clearly shows that the overall black hole number density in the Universe is fairly high.” https://lnkd.in/d8Jh7TB View in LinkedIn

NO HEN’S TOOTH. “Stellar-remnant black holes should be abundant in the local Universe.” https://lnkd.in/d8Jh7TB View in LinkedIn

“RINGWOODITE is the most common mineral phase in the lower transition zone of the Earth’s mantle, at depths of 525 to 660 km. This ringwoodite crystal contains about 1% water. If the whole ringwoodite of the mantle contains this amount of water, it is estimated that there is almost three times as much water in the mantle as in all the oceans combined.” https://lnkd.in/dNuAzU2 View in LinkedIn

Bougainvillea jumping genes causing electric strawberry on white background in the same plant. View in LinkedIn

ROLE IN EVOLUTION. “Recently through a series of observations it has been shown that supermassive black holes (SMBH) residing at the center of galaxies play a significant role in cosmic evolution of structure in the Universe.” https://lnkd.in/dq-SEai View in LinkedIn