Re: Room Escape Contest 2 Level 3
Raiquen Courcelle
Can you escape the room? Each room is different, Some are more challenging escaping than others. It is a fun game made for escape game lovers. If you are stuck you can buy/use coins to proceed further, But here I will show you how to solve each level easily. The purpose of this game is to escape from the shut-up room.
You can click the screen, in order to find hints and items. If you click an item, you can find details related to it. You can choose other items during a detailed picture display.
Precision measurements of the anisotropies in the Cosmic Microwave Background (CMB) have become one of the cornerstones of modern cosmology. One major objective of current CMB experiments is the discovery of a stochastic background of gravitational waves generically produced by theories of cosmic inflation. Such a signal could be detected as an excess of odd-parity polarization in the CMB at degree angular scales. The South Pole Observatory is a coordinated effort between the South Pole Telescope (SPT) and the BICEP/Keck collaborations that will use the synergies of the two experiments to search for this signal in the presence of galactic and gravitational lensing foregrounds with unprecedented sensitivity. In this talk I will discuss some recent and upcoming results from both projects focusing on the search for inflationary gravitational waves in the CMB.
Recent observations of galaxies and star clusters have highlighted the need for systematic studies dedicated to exploring the impact of uncertain parameters of stellar evolution on the properties of stellar populations. While the use of fitting formulae to stellar tracks remains a popular choice for modelling stellar evolution in population synthesis codes, they are not adaptable to changes in the stellar tracks. In this talk, I will present results from an alternative approach, METISSE, which uses interpolation between sets of pre-computed stellar tracks to approximate evolution parameters for a population of stars. It can readily make use of stellar models computed with different stellar evolution codes and can compare their predictions for populations of stars. Using METISSE with the data from two different stellar evolution codes, I will show how different physical ingredients used in the evolution of massive stars, such as the treatment of their radiation dominated envelopes, can lead to differences in their evolutionary properties. These differences are important as they can help us account for observations of the stellar populations and the formation of gravitational wave progenitors.
Simulations are now allowing us to probe the scales of the CGM (circumgalactic medium) around galaxies in order to look at the influence of realistic galaxy formation processes. However, it is apparent that the properties of the multi-phase CGM are not yet converged in simulations (e.g. Van de Voort et al., 2019; Hummels et al., 2019), hence their reliability to make predictions is still in question. It is also clear the CGM plays a key role in the evolution of a galaxy; it is a supply of gas for star formation and a key site for feedback-generated outflows, along with the recycling of baryons (for a recent review see Tumlinson et al., 2017).
Weak gravitational lensing provides an observational avenue to determine the relation between the halo mass and stellar mass of a galaxy. While we expect two galaxies with the same stellar mass to have different halos, at the moment, existing weak lensing studies are only sensitive to an average halo mass. In this talk, I will present an end-to-end methodology to measure the effects of weak lensing on individual galaxy-galaxy systems exploiting their kinematic information. I will present the results of analysing 21 weakly lensed systems and present ways to overcome weak lensing limitations and be sensitive to the dispersion in halo masses.
Understanding the sources responsible for driving reionization has been a major goal in astrophysics for many years. One critical measurement required is the ionizing (or Lyman continuum, LyC) escape fraction from observed galaxy samples. A major difficulty arises from the level of transmission of LyC through the intergalactic medium (IGM), an unknown (but essential) quantity in the calculation of LyC escape from individual sources. The typical method is to assume an average transmission value based on consideration of HI column density distribution functions, but is this appropriate? In general, observational surveys at high redshift are strongly biased towards the brightest objects as these are the easiest to detect. Given the fact that LyC emission is remarkably faint, we should expect to only detect those galaxies with the highest emergent LyC flux. This, in turn, suggests that detections of LyC in surveys will be biased towards IGM sightlines with higher than average transmission of ionizing photons. In this talk I discuss the quantification of this IGM transmission bias for LyC detections and explore the implications when considering the recovered LyC escape values from current surveys. Careful consideration of such biases will be critical in understanding how LyC escape depends on galaxy properties, which ultimately colours our understanding of how reionization proceeds.
The quest for the origin of the elements in the universe combines different fields of physics and astronomy, from the smallest scales of nuclear reactions to large scales of giant stars. To understand the chemical history of our universe the abundances of elements heavier than iron are observed in the photospheres of old stars. The vast majority of heavy elements are formed by the slow (s) and rapid (r) neutron-capture processes. However, some observations of heavy-element abundance patterns of old stars are incompatible with either of these processes or even a combination of both.
I will show that these puzzling heavy-element patterns can be explained as the result of a separate neutron-capture process operating at neutron densities intermediate to the s and r process: the i process. Comparing theoretical predictions of i-process nucleosynthesis with the observed abundance patterns gives us new insights into uncertain phases of stellar evolution and will ultimately help us understand the origin of the elements in our universe.
The first neutron star merger observed with gravitational waves and in electromagnetic radiation confirmed that binary neutron star mergers are the progenitors of at least some short gamma-ray bursts. The multi-messenger observations have been used to a probe a lot of fundamental physics, however, despite the wealth of observations the fate of the remnant of GW170817 is still uncertain. I will give an overview of binary neutron star mergers focussing on the nature of the remnant from observations of short gamma-ray bursts and theoretical considerations. I will discuss the implications of these observations on the nuclear equation of state, neutron star dynamics and gamma-ray bursts.
The physics of gravity on cosmological scales affects both the rate of assembly of galaxy large-scale structure, and the gravitational lensing of background light through this cosmic web. By comparing the amplitude of these different observational signatures, we can construct tests that can distinguish General Relativity from its potential modifications. We use the latest weak gravitational lensing dataset from the Kilo-Degree Survey, KiDS-1000, in conjunction with overlapping galaxy redshift surveys, to perform the most accurate existing amplitude ratio test on projected scales up to 100 Mpc/h. The scale-independence and redshift-dependence of these measurements are consistent with the theoretical expectation of General Relativity in a Universe with matter density Omega_m = 0.27 +/- 0.04. We demonstrate that our results are robust against different analysis choices, including schemes for correcting the effects of source photometric redshift errors.
One of the most uncertain aspects related to our understanding of the end points of stellar evolution is the link between the progenitor star and the nature of the supernova explosion that the progenitor will undergo. Even though hundreds of supernovae are discovered each year by optical surveys, these sources are usually too distance to resolve the ejecta and immediate surrounding of the exploded star. However, due to their long lifetimes and close proximity, supernova remnants which are the long lived structures that results from the supernova explosion of either a white dwarf or a massive star, provide us with a unique opportunity to study supernova explosion and dynamics up close and in detail. In this talk, I will highlight some recent advances that have been made in the understanding of supernovae and their progenitors using wavelength studies of supernova remnants.
I will showcase recent results from resolved multi-tracer (FIR, CO, C+) studies of dust and gas in z>2 SMGs at (k)pc resolution. Combining the superb angular resolution and high-frequency capabilities of ALMA, gravitational lensing and radiative transfer modelling, our results provide an unprecedented view of the conditions in these extreme star factories down to 50-pc scales .
In this talk I will summarise recent results of the dependence of the galaxy stellar-to-halo mass relation on galaxy morphology. We use data from the Sloan Digital Sky Survey DR7 with morphological classifications from Galaxy Zoo, and also compare with the EAGLE cosmological simulation, to draw a coherent physical picture of the different evolutionary paths of discs and ellipticals. I will also explore possible scenarios of galaxies undergoing morphological transformation and quenching. To finalise I will discuss the limitations of current simulations such as EAGLE, and introduce the ongoing simulation project of EAGLE-2.
d3342ee215