Symbol z_s
is part of the quantity the equation computes from the expression on the right.
Read this term in its guide →Published equation contexts
Why this formula appears here
The relation itself is old and simple. For a spherical, non-rotating exterior, the surface redshift follows from the mass M and radius R as . — a function of the star’s compactness alone, so that whatever fraction of a percent of uncertainty NICER puts on M and R propagates directly into the redshift. The paper works through six NICER-mapped pulsars this way, and two of them mark the range worth remembering. PSR J0740+6620, the most massive precisely-timed neutron star known, comes in at roughly 2.07\, with a radio-timing mass fixed independently by Shapiro delay to 2.080.07\, [ 4 ] , giving a compactness near 0.25 and a surface redshift 0.40…
Read the representative guide
Symbol G
G occurs above the fraction bar. The numerator is divided by the entire denominator below it.
Read this term in its guide →Symbol M
M occurs above the fraction bar. The numerator is divided by the entire denominator below it.
Read this term in its guide →Symbol R
R occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.
Read this term in its guide →Denominator: Rc^2
The complete quantity below the fraction bar; it must be nonzero for this division.
Read this term in its guide →How to interpret it
With a fixed numerator, increasing a nonzero denominator reduces the fraction. Read it with the definitions, units, and assumptions supplied by the article.
Research cited beside this formula
Published contexts (1)
A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.
Equation 4 · Crossed Fields
A Neutron Star Is a Redshift Standard
This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.
The relation itself is old and simple. For a spherical, non-rotating exterior, the surface redshift follows from the mass M and radius R as . — a function of the star’s compactness alone, so that whatever fraction of a percent of uncertainty NICER puts on M and R propagates directly into the redshift. The paper works through six NICER-mapped pulsars this way, and two of them mark the range worth remembering. PSR J0740+6620, the most massive precisely-timed neutron star known, comes in at roughly 2.07\, with a radio-timing mass fixed independently by Shapiro delay to 2.080.07\, [ 4 ] , giving a compactness near 0.25 and a surface redshift 0.40…
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