A Is M_{Pl} the Planck mass or the reduced Planck mass?

[Alpha2021]

What is the value of M_{Pl} used in the Planck (CMB) collaboration's observation papers, such as the one referenced in this link: https://arxiv.org/pdf/1807.06211.pdf. Specifically, I am wondering if it refers to the Planck mass or the reduced Planck mass?

 

[anuttarasammyak]

According to NIST webpage of https://physics.nist.gov/cgi-bin/cuu/Value?plkm , it is 2.176 434 x 10-8 kg.

What is the "reduced" planck mass you mean ?

 

[Alpha2021]

Thanks for your kind reply.
Definition of reduced Planck mass can be found here.
The problem is that M_{Pl} is used in the literature interchangeably as Planck mass or reduced Planck mass. Did you see anywhere in Planck's papers where they define M_{Pl}?

 

[anuttarasammyak]

I found in

https://www.cosmos.esa.int/web/planck
> https://www.aanda.org/articles/aa/full_html/2020/09/aa33910-18/aa33910-18.html#S1

You may get value of m_pl they use.

 

[Alpha2021]

Thank you very much for your help.

I found in

https://www.cosmos.esa.int/web/planck
> https://www.aanda.org/articles/aa/full_html/2020/09/aa33910-18/aa33910-18.html#S1
View attachment 325894
You may get value of m_pl they use.

 

[ohwilleke]

What is the value of M_{Pl} used in the Planck (CMB) collaboration's observation papers, such as the one referenced in this link: https://arxiv.org/pdf/1807.06211.pdf. Specifically, I am wondering if it refers to the Planck mass or the reduced Planck mass?

Better practice, although you are right in asking as some authors are sloppy in their typesetting, is to indicate the reduced Planck mass with diagonal line through the letters P or Pl in the subscript, just as one indicates the reduced Planck's constant with a diagonal link through the symbol "h" for Planck's constant.