Roentgenium
Stability and half-lives

Isotope
Half-life
Half-life
Half-life
Decay mode
Discovery year
Discovery reaction
Isotope
Recent publications
Ref
NUBASE 2016
Decay mode
Discovery year
Discovery reaction
272Rg
3.8 ms
-
4.5 ms
α
1994
209Bi(64Ni,n)
274Rg
14 ms
-
29 ms
α
2004
278Nh(—,α)
278Rg
4.2 ms
-
8 ms
α
2006
282Nh(—,α)
279Rg
90 ms
-
180 ms
α
2003
287Mc(—,2α)
280Rg
4.6 s
-
4.3 s
α, EC
2003
288Mc(—,2α)
281Rg
17 s
-
24 s
SF, α
2010
293Ts(—,3α)
282Rg
1.7 min
-
1.6 min
α
2010
294Ts(—,3α)
283Rg
5.1 min
-
—
SF
1999
283Cn(e−,νe)
286Rg
10.7 min
-
—
α
1998
290Fl(e−,νeα)

Question: How many isotopes of roentgenium have been reported with masses of 272, 274, 278–283, and 286?
Answer: Nine different isotopes of roentgenium have been reported with masses of 272, 274, 278–283, and 286.