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A galaxy cluster is an astronomical structure that contains anywhere from hundreds to thousands of galaxies bound togeth

Posted: Thu Jul 14, 2022 4:52 pm
by answerhappygod
A galaxy cluster is an astronomical structure that containsanywhere from hundreds to thousands of galaxies bound together bygravity. Measurements of log-intensity (log number of photons) fromsmall patches of the sky can be used to determine whether or not agalaxy cluster exists at a certain location. Galaxy clusters willemit a log-intensity that follows a normal distribution with mean10 units and standard deviation 3 units. A logintensity measurementfrom a part of the sky with no galaxy cluster present isdistributed normally with mean 1 unit and standard deviation 1unit. While there is no way of actually knowing if a galaxy clusteris located in a particular patch, an observation will be consideredas having a galaxy cluster if the measured log-intensity has lessthan 0.02 probability of having come from a patch without a galaxycluster. It is thought that the probability of a measurementactually being from a galaxy cluster is 0.01. i. Calculate theprobability that an observation is considered as having a galaxycluster. ii. Calculate the probability that an observation withlog-intensity measurement greater than 3 units is from a galaxycluster.
A Galaxy Cluster Is An Astronomical Structure That Contains Anywhere From Hundreds To Thousands Of Galaxies Bound Togeth 1
A Galaxy Cluster Is An Astronomical Structure That Contains Anywhere From Hundreds To Thousands Of Galaxies Bound Togeth 1 (141.14 KiB) Viewed 38 times
e) (16 pts.) A galaxy cluster is an astronomical structure that contains anywhere from hundreds to thousands of galaxies bound together by gravity. Measurements of log-intensity (log number of photons) from small patches of the sky can be used to determine whether or not a galaxy cluster exists at a certain location. Galaxy clusters will emit a log-intensity that follows a normal distribution with mean 10 units and standard deviation 3 units. A logintensity measurement from a part of the sky with no galaxy cluster present is distributed normally with mean 1 unit and standard deviation 1 unit. While there is no way of actually knowing if a galaxy cluster is located in a particular patch, an observation will be considered as having a galaxy cluster if the measured log-intensity has less than 0.02 probability of having come from a patch without a galaxy cluster. It is thought that the probability of a measurement actually being from a galaxy cluster is 0.01. i. Calculate the probability that an observation is considered as having a galaxy cluster. ii. Calculate the probability that an observation with log-intensity measurement greater than 3 units is from a galaxy cluster.